bluuebunny/crossref_metadata_2025 huggingface dataset:
Bridging the gap between in silico and cell‐based analysis of the nuclear factor‐κB signaling pathway by in vitro studies of IKK2
Authors: Ihekwaba Adaoha E. C. , Wilkinson Stephen J. , Waithe Dominic , Broomhead David S. , Li Peter , Grimley Rachel L. , Benson Neil
Published: February 2007

Previously, we have shown by sensitivity analysis, that the oscillatory behavior of nuclear factor (NF‐κB) is coupled to free IkappaB kinase‐2 (IKK2) and IkappaBalpha(IκBα), and that the phosphorylation of IκBα by IKK influences the amplitude of NF‐κB oscillations. We have performed further analyses of the behavior of NF‐κB and its signal transduction network to understand the dynamics of this system. A time lapse study of NF‐κB translocation in 10 000 cells showed discernible oscillations in levels of nuclear NF‐κB amongst cells when stimulated with interleukin (IL‐1α), which suggests a small degree of synchronization amongst the cell population. When the kinetics for the phosphorylation of IκBα by IKK were measured, we found that the values for the affinity and catalytic efficiency of IKK2 for IκBα were dependent on assay conditions. The application of these kinetic parameters in our computational model of the NF‐κB pathway resulted in significant differences in the oscillatory patterns of NF‐κB depending on the rate constant value used. Hence, interpretation of in silico models should be made in the context of this uncertainty.
Vaccination with prion peptide‐displaying papillomavirus‐like particles induces autoantibodies to normal prion protein that interfere with pathologic prion protein production in infected cells
Authors: Handisurya Alessandra , Gilch Sabine , Winter Dorian , Shafti‐Keramat Saeed , Maurer Dieter , Schätzl Hermann M. , Kirnbauer Reinhard
Published: February 2007

Prion diseases are fatal neurodegenerative disorders caused by proteinaceous infectious pathogens termed prions (PrPSc). To date, there is no prophylaxis or therapy available for these transmissible encephalopathies. Passive immunization with monclonal antibodies recognizing the normal host‐encoded prion protein (PrPC) has been reported to abolish PrPSc infectivity and to delay onset of disease. Because of established immunologic tolerance against the widely expressed PrPC, active immunization appears to be difficult to achieve. To overcome this limitation, papillomavirus‐like particles were generated that display a nine amino acid B‐cell epitope, DWEDRYYRE, of the murine/rat prion protein in an immunogenic capsid surface loop, by insertion into the L1 major capsid protein of bovine papillomavirus type 1. The PrP peptide was selected on the basis of its previously suggested central role in prion pathogenesis. Immunization with PrP–virus‐like particles induced high‐titer antibodies to PrP in rabbit and in rat, without inducing overt adverse effects. As determined by peptide‐specific ELISA, rabbit immune sera recognized the inserted murine/rat epitope and also cross‐reacted with the homologous rabbit/human epitope differing in one amino acid residue. In contrast, rat immune sera recognized the murine/rat peptide only. Sera of both species reacted with PrPC in its native conformation in mouse brain and on rat pheochromocytoma cells, as determined by immunoprecipitation and fluorescence‐activated cell sorting analysis. Importantly, rabbit anti‐PrP serum contained high‐affinity antibody that inhibited de novo synthesis of PrPSc in prion‐infected cells. If also effective in vivo, PrP–virus‐like particle vaccination opens a unique possibility for immunologic prevention of currently fatal and incurable prion‐mediated diseases.
Modeling Natural Attenuation with Source Control at a Chlorinated Solvents Dry Cleaner Site
Authors: Ling Meng , Rifai Hanadi S.
Published: February 2007

A ground water flow and solute transport model was developed for a site contaminated with chlorinated solvents to simulate the site remediation activities that included natural attenuation and source control. MODFLOW was used to model the flow field, and RT3D was employed to simulate the sequential decay reactions involving perchloroethene, trichloroethene, dichloroethene, and vinyl chloride (VC). Predictive simulations were completed for two conditions: natural attenuation alone and source excavation followed by natural attenuation. Results demonstrated the feasibility of site remediation for both conditions with the latter one occurring in a shorter time frame. A detailed sensitivity analysis was performed to assess the uncertainty in model predictions. The most sensitive model parameters (i.e., initial contaminant concentrations, reaction rate constants, and source release rates) were perturbed and combined to form a number of parameter sets for use in the predictive simulations. The maximum plume length, the maximum plume concentration, and the persistence time for the noncompliance plume area were assessed to identify the possible failure scenarios and the most likely future plume configuration. Results indicated that further VC plume expansion or migration beyond site boundaries is unlikely.
Zero‐Valent Iron Emplacement in Permeable Porous Media Using Polymer Additions
Authors: Oostrom M. , Wietsma T.W. , Covert M.A. , Vermeul V.R.
Published: February 2007

At the Hanford Site in Washington, an extensive in situ redox manipulation (ISRM) permeable reactive barrier was installed to prevent chromate from reaching the Columbia River. However, chromium has been detected in several wells, indicating a premature loss of the reductive capacity in the aquifer. One possible cause for premature chromate breakthrough is associated with the presence of high‐permeability zones in the aquifer. The potential emplacement of zero‐valent iron (Fe0) into high‐permeability Hanford sediments to enhance the barrier’s reductive capacity using shear‐thinning fluids containing polymers was investigated in three‐dimensional wedge‐shaped aquifer models. Porous media were packed in the wedge‐shaped flow cell to create either a heterogeneous layered system with a high‐permeability zone between two low‐permeability zones or a high‐permeability channel surrounded by low‐permeability materials. The injection flow rate, polymer type, polymer concentration, and injected pore volumes were determined based on preliminary short‐ and long‐column experiments. The flow cell experiments indicated that iron concentration enhancements of at least 0.6% w/w could be obtained using moderate flow rates and injection of 30 pore volumes. The aqueous pressure increased by a maximum of 25 kPa during infiltration, but a decrease in permeability was not observed. Under optimal conditions, the 0.6% amended Fe0 concentration would provide approximately 20 times the average reductive capacity that is provided by the dithionite‐reduced Fe(II) in the ISRM barrier.
Optimization of Radioimmunotherapy of Solid Tumors: Biological Impediments and Their Modulation
Authors: Jain Maneesh , Venkatraman Ganesh , Batra Surinder K.
Published: February 2007

In contrast to the overwhelming success of radiolabeled antibodies in treating hematologic malignancies, only modest success has been achieved in the radioimmunotherapy of solid tumors. One of the major limitations in successful application of radioimmunotherapy is the large molecular size of the intact immunoglobulin that results in prolonged serum half-life and poor tumor penetration and uptake. With the advent of antibody engineering, small molecular weight antibody fragments exhibiting improved pharmacokinetics and tumor penetration have been generated. However, their clinical application has been limited by suboptimal tumor uptake and short tumor residence time. There is a greater realization that optimization of the molecular size of the antibodies alone is not sufficient for clinical success of radioimmunotherapy. In addition to their size, radiolabeled antibodies encounter other impediments before reaching their target antigens expressed on the cell surface of solid tumors. Some of the barriers include poor blood flow in large tumors, permeability of vascular endothelium, elevated interstitial fluid pressure of tumor stroma, and heterogeneous antigen expression. Recent research has considerably improved our understanding and appreciation of these forces, and the new wave of optimization strategies involves the use of biological modifiers to modulate the impediments posed by solid tumors. In combination with radiolabeled antibodies, various agents are being used to improve the tumor blood flow, enhance vascular permeability, lower tumor interstitial fluid pressure by modulating stromal cells and extracellular matrix components, up-regulate the expression of target antigens, and improve the penetration and retention of the radiopharmaceuticals. This review outlines ongoing research efforts involving biological modifiers to optimize the uptake and efficacy of radiolabeled antibodies for the treatment of solid tumors.
Nitroxyl Anion Donor, Angeli’s Salt, Does Not Develop Tolerance in Rat Isolated Aortae
Authors: Irvine Jennifer C. , Favaloro Joanne L. , Widdop Robert E. , Kemp-Harper Barbara K.
Published: February 2007

The nitroxyl anion (HNO) is emerging as a novel regulator of cardiovascular function with therapeutic potential in the treatment of diseases such as heart failure. It remains unknown whether tolerance develops to HNO donors, a limitation of currently used nitrovasodilators. The susceptibility of the HNO donor, Angeli’s salt (AS), to the development of vascular tolerance was compared with the NO donors, glyceryl trinitrate (GTN) and diethylamine/NONOate (DEA/NO) in rat isolated aortae. Vasorelaxation to AS was attenuated (P<0.01) by the HNO scavengerl-cysteine, whereas the sensitivity to GTN and DEA/NO was decreased (P<0.01) by the NO· scavenger carboxy-[2-(4-carboxyphenyl)-4,4,5,5-tetramethyl-imidozoline-1-oxy-3-oxide]. The soluble guanylate cyclase inhibitor 1H-[1,2,4]oxadiazolo[4,3-a]quinoxaline-1-one impaired responses to GTN≥AS≫DEA/NO. Pretreatment with 10, 30, and 100 μmol/L of GTN for 60 minutes induced a 4- (P<0.05), 13- (P<0.01), and 48-fold (P<0.01) decrease in sensitivity to GTN, demonstrating tolerance development. In contrast, pretreatment with AS or DEA/NO (10, 30, and 100 μmol/L) did not alter their subsequent vasorelaxation. All of the nitrovasodilators (30 μmol/L) displayed a similar time course of vasorelaxation and cGMP accumulation over a 60-minute period. Unlike vasorelaxation, the magnitude of peak cGMP accumulation differed substantially: DEA/NO≫AS>GTN. GTN did not induce cross-tolerance to either AS or DEA/NO. In contrast, pre-exposure to DEA/NO, but not AS, caused a concentration-dependent attenuation (P<0.01) of GTN-mediated relaxation, which was negated by the protein kinase G inhibitor guanosine 3′,5′-cyclic monophosphorothioate, 8-(4-chlorophenylthio)-,Rp-isomer, triethylammonium salt. In conclusion, vascular tolerance does not develop to HNO, nor does cross-tolerance between HNO and GTN occur. Thus, HNO donors may have therapeutic advantages over traditional nitrovasodilators.
Glutamatergic Inputs in the Hypothalamic Paraventricular Nucleus Maintain Sympathetic Vasomotor Tone in Hypertension
Authors: Li De-Pei , Pan Hui-Lin
Published: February 2007

The paraventricular nucleus (PVN) of the hypothalamus is critical to the regulation of sympathetic output. The PVN hyperactivity is known to cause increased sympathetic nerve activity in spontaneously hypertensive rats (SHRs). The purpose of this study was to determine whether glutamatergic input to the PVN contributes to heightened sympathetic outflow in hypertension. Lumbar sympathetic nerve activity, mean arterial blood pressure, and heart rate were recorded from anesthetized SHRs and Wistar-Kyoto (WKY) rats. Bilateral microinjection of an N-methyl-D-aspartate receptor antagonist, 2-amino-5-phosphonopentanoic acid, or a non-N-methyl-D-aspartate receptor antagonist, 6-cyano-7-nitroquinoxaline-2,3-dione, into the PVN dose-dependently decreased lumbar sympathetic nerve activity, mean arterial blood pressure, and heart rate in SHRs but not in WKY rats. Bilateral microinjection of kynurenic acid into the PVN also significantly decreased lumbar sympathetic nerve activity, mean arterial blood pressure, and heart rate in SHRs but not in WKY rats. Furthermore, microinjection of gabazine, a specific GABA
A
receptor antagonist, into the PVN increased lumbar sympathetic nerve activity, mean arterial blood pressure, and heart rate in both SHRs and WKY rats. Notably, this response was significantly attenuated in SHRs compared with that in WKY rats. In addition, kynurenic acid abolished the sympathoexcitatory and pressor responses to microinjection of gabazine into the PVN in both SHRs and WKY rats. Thus, this study provides new functional evidence that resting sympathetic vasomotor tone is maintained by tonic glutamatergic input in the PVN in SHRs. Removal of GABAergic inhibition results in augmented glutamatergic input in the PVN, which probably constitutes an important source of excitatory drive to the brain stem vasomotor neurons in hypertension.
Pregnancy-Induced Hypertension in Women Who Were Born Small
Authors: Rasmussen Svein , Irgens Lorentz M.
Published: February 2007

We assessed whether a pregnant woman who was born small for gestational age has increased risk of pregnancy-induced hypertension (PIH), and whether the same applies to a pregnant partner of a man who was born small for gestational age. We linked generational data from the medical birth registry of Norway (1967–2005). Female and male newborns were identified as parents with 197 716 and 131 959 first or second pregnancies from 1998 to 2005, respectively. In the first pregnancy in women who were born with birth weight <2.5, 2.5 to 4.9, and 5 to 9.9 birth weight percentiles, odds ratios of PIH in general adjusted for smoking and maternal age were 1.5, 1.4, and 1.1, respectively, compared with percentile 25 to 75. In the second pregnancy, corresponding odds ratios were 1.5, 1.3, and 1.2, respectively. A similar trend was found in all of the subgroups of PIH. Women who were born below the 5th birth weight percentile were 2 to 3 times more likely to have preeclampsia with onset before 34 weeks of gestation than those with birth weight between the 25th and 75th percentiles (adjusted odds ratios: 1.8 to 2.8). Father’s birth weight for gestational age was not associated with mother’s development of PIH. In conclusion, women who were born growth restricted after normotensive pregnancies were more likely to develop PIH later in life. The lack of association with the father’s size at birth agrees with the hypothesis of fetal environmental origin of PIH, although maternal genetic transmission of susceptibility for PIH cannot be ruled out.
The Chinese GDP Growth Rate Puzzle: How Fast Has the Chinese Economy Grown?
Authors: Wu Harry X.
Published: February 2007

The Chinese statistical authorities recently revised the Chinese GDP level and real growth rate for the period 1993–2004 following China's first national economic census for 2004. However, the methodology used in their revision is opaque. Using a trend- deviation interpolation approach, this study has managed to replicate the basic procedures of the revision and reproduced the official estimates. Through this exercise, we have found that the estimates that could be obtained by the straightforward interpolation procedures were significantly modified. Based on a political economy argument, we attempt to explain why the revision had to leave the growth rate of 1998 intact and why it had to bypass the price issue and directly work on the real growth rate revision. Based on previous studies and other observations, we also question the census results on non-service industries.
External Finance and Investment Climate in East Asia and Other Emerging Markets: What Really Matters?
Authors: Negishi Shoko
Published: February 2007

Developing countries are facing new competitive challenges to attract sufficient external financing to sustain their growth. This paper attempts to answer the question: How can a country attract more long-term, stable foreign investment? Our study shows the increasing role of a political risk factor as a driver of foreign direct investment (FDI) inflows, and suggests that reduced financial risk after the East Asian crisis might have led to a substitution of FDI with capital market flows. Our study also shows the importance of fostering sound regulatory systems and good institutions for attracting FDI, for example, establishing a stable government that implements economic policy effectively and reduces uncertainty associated with internal disorder and a lack of democratic regime. The simulation exercise suggests that an improved investment climate would increase FDI by 7 percent and would benefit China most.
Determinants of Nuclear Weapons Proliferation
Authors: Jo Dong-Joon , Gartzke Erik
Published: February 2007

Nuclear weapons proliferation is a topic of intense interest and concern among both academics and policy makers. Diverse opinions exist about the determinants of proliferation and the policy options to alter proliferation incentives. We evaluate a variety of explanations in two stages of nuclear proliferation, the presence of nuclear weapons production programs and the actual possession of nuclear weapons. We examine proliferation quantitatively, using data collected by the authors on national latent nuclear weapons production capability and several other variables, while controlling for the conditionality of nuclear weapons possession based on the presence of a nuclear weapons program. We find that security concerns and technological capabilities are important determinants of whether states form nuclear weapons programs, while security concerns, economic capabilities, and domestic politics help to explain the possession of nuclear weapons. Signatories to the Treaty on the Non-Proliferation of Nuclear Weapons (NPT) are less likely to initiate nuclear weapons programs, but the NPT has not deterred proliferation at the system level.
Introduction
Authors: Purdy Sean , Kwak Nancy H.
Published: February 2007

This article introduces a special issue on the history of public housing in the Americas, with contributions on the United States, Canada, the Caribbean, and Argentina. It briefly surveys the state of public housing in the Americas and the contrasts and parallels between countries as well as between developed and developing regions; it stresses the political and social importance of state housing provision during the urban crises of the twentieth century; and it broadly charts the historiographical trends. In introducing the various articles that deal with the history of public housing and public housing tenants in Los Angeles, San Francisco, Toronto, Buenos Aires, Puerto Rico, and Barbados, the article highlights the shift away from narrow policy histories to interpretations set in broader political, economic, social, and transnational contexts that use diverse primary sources such as oral testimony. It also highlights the crucial role played by historical actors such as public housing tenants themselves and the media.
“The Right to a Home”
Authors: Aboy Rosa
Published: February 2007

Between 1946 and 1955, Juan Perón's government built more houses for the most impoverished sectors of Argentina society than ever before. This article explores the articulation of the state housing policy with the experience of the inhabitants who received homes built by the Peronist state. In a sense, the houses were a testing lab for new ways of daily life. Their inhabitants frequently experienced in only a few years a transition that usually demanded decades. The family model shifted from the traditional family to the nuclear model, maintaining the traditional roles of the male provider and the female dedicated to motherhood and home. Using oral testimony, this analysis highlights the connection between politics and individual experience at a microhistoriographical level, allowing for the contextualization of Peronist public housing policies and analyzing the continuities with their predecessors as well as the way in which they channeled contradictory political ideologies and architectural sensibilities.
Where will the People Go
Authors: Brushett Kevin
Published: February 2007

In the late 1940s and early 1950s, Canadian cities dealt with a growing housing shortage while the federal and provincial governments argued over who would implement the provisions of the 1944 National Housing Act. This was particularly true in Toronto. As Torontonians celebrated the construction of Regent Park, Canada's “Premier Slum Clearance and Public Housing Project,” nearly 1,350 Toronto families were housed in dilapidated old army barracks and staff houses. Until Regent Park, the shelters were Toronto's only rent-geared-to-income housing project. This article challenges the assumptions that Toronto's homeless were “shiftless welfare bums” and examines the strategies shelter residents used to survive the often brutal conditions in which they lived and how they hoped to escape them. Finally, it argues that the inability of municipalities to replace emergency shelters with decent affordable housing reveals the long-standing reluctance of Canadian governments to develop social-housing programs to eliminate homelessness.
Links Among Attachment Dimensions, Affect, the Self, and Perceived Support for Broadly Generalized Attachment Styles and Specific Bonds
Authors: Barry Robin A. , Lakey Brian , Orehek Edward
Published: February 2007

Measures of adult attachment reflect both respondents' broadly generalized styles as well as bonds with specific attachment figures. Using Cronbach, Gleser, Nanda, and Rajaratnam's (1972) Multivariate Generalizability analyses, the authors estimated the extent to which correlations among attachment, affect, the self, and perceived social support occurred for both styles and bonds. In two studies, participants rated attachment, affect, the self, and perceived support when thinking about their mothers, fathers, and romantic partners. In both studies, attachment dimensions reflected specific bonds much more so than generalized styles. When correlations reflected specific bonds, both anxious and avoidant dimensions were strongly linked to high negative affect, low positive affect, and low perceived support. In contrast, evidence for links between attachment and affect was inconclusive when correlations reflected generalized styles. Links between attachment and the self depended on the type of self-construct and whether styles or bonds were analyzed.
Group Identification and Historical Memory
Authors: Sahdra Baljinder , Ross Michael
Published: February 2007

Differences in ingroup identification can influence the accessibility of historical memories. In Study 1, the authors examined individual differences in identity; in Study 2 they experimentally manipulated identity. In Study 1, high identifiers recalled fewer incidents of ingroup violence and hatred than did low identifiers. High and low identifiers did not differ in their recall of ingroup suffering. In Study 2, participants in the high-identity condition recalled fewer incidents of violence and hatred by members of their group than did those in the low-identity condition but a similar number of good deeds. Control participants recalled more positive than negative group actions; this bias was exaggerated in the high-identity condition and eliminated in the low-identity condition. The authors interpret the results as indicating the effects of social identity on individual-level memory processes, especially schema-consistent recall. They evaluate other explanations of the bias, including collective censorship of negative histories.
The Importance of Conscientiousness in Adolescent Interpersonal Relationships
Authors: Jensen-Campbell Lauri A. , Malcolm Kenya T.
Published: February 2007

This research examined how conscientiousness contributes to adolescents' positive peer relationships and vulnerability to poorer ones. Given its temperamental origins in effortful control, conscientiousness was expected to be particularly important. A total of 256 fifth to eighth graders completed personality, peer-relationship, and victimization measures. Peers, parents, and teachers also completed assessments. Adolescents higher on conscientiousness experienced less victimization, better quality friendships, and higher peer acceptance even after controlling for the other Big Five dimensions. Externalizing and/or attention problems mediated the link between conscientiousness and peer relations. Conscientiousness moderated the relation between internalizing problems and poor interpersonal functioning. Results suggest that self-control processes associated with conscientiousness are important in developing and maintaining relationships in adolescence.
Implications of Counterfactual Structure for Creative Generation and Analytical Problem Solving
Authors: Markman Keith D. , Lindberg Matthew J. , Kray Laura J. , Galinsky Adam D.
Published: February 2007

In the present research, the authors hypothesized that additive counterfactual thinking mind-sets, activated by adding new antecedent elements to reconstruct reality, promote an expansive processing style that broadens conceptual attention and facilitates performance on creative generation tasks, whereas subtractive counter-factual thinking mind-sets, activated by removing antecedent elements to reconstruct reality, promote a relational processing style that enhances tendencies to consider relationships and associations and facilitates performance on analytical problem-solving tasks. A reanalysis of a published data set suggested that the counterfactual mind-set primes previously used in the literature tend to evoke subtractive counterfactuals. Studies 1 and 2 then demonstrated that subtractive counterfactual mind-sets enhanced performance on analytical problem-solving tasks relative to additive counterfactual mind-sets, whereas Studies 3 and 4 found that additive counterfactual mind-sets enhanced performance on creative generation tasks relative to subtractive counterfactual mind-sets.
Good Feelings in Christianity and Buddhism: Religious Differences in Ideal Affect
Authors: Tsai Jeanne L. , Miao Felicity F. , Seppala Emma
Published: February 2007

Affect valuation theory (AVT) predicts cultural variation in the affective states that people ideally want to feel (i.e., “ideal affect”). National and ethnic comparisons support this prediction: For instance, European Americans (EA) value high arousal positive (HAP) states (e.g., excitement) more and low arousal positive (LAP) states (e.g., calm) less than Hong Kong Chinese. In this article, the authors examine whether religions differ in the ideal affective states they endorse. The authors predicted that Christianity values HAP more and LAP less than Buddhism. In Study 1, they compared Christian and Buddhist practitioners' ideal affect. In Studies 2 and 3, they compared the endorsement of HAP and LAP in Christian and Buddhist classical texts (e.g., Gospels, Lotus Sutra) and contemporary self-help books (e.g., Your Best Life Now, Art of Happiness). Findings supported predictions, suggesting that AVT applies to religious and to national and ethnic cultures.
Liberty and Justice for All? Implications of Exposure to the U.S. Flag for Intergroup Relations
Authors: Butz David A. , Plant E. Ashby , Doerr Celeste E.
Published: February 2007

Three studies examined the implications of nationalistic ideologies and exposure to the U.S. flag for the activation of egalitarian concepts and outgroup hostility. Study 1 demonstrated that subliminal exposure to the U.S. flag activated participants' egalitarian concepts. In Study 2, highly nationalistic participants who were exposed to the U.S. flag reported less hostility than did those not exposed to the flag, whereas the flag did not influence the hostility of participants low in nationalism. Study 3 demonstrated that for participants high in nationalism, greater activation of egalitarian concepts on subliminal exposure to the U.S. flag was associated with less hostility toward Arabs and Muslims in the presence of the U.S. flag. The theoretical and practical implications of these findings are discussed.
Transformations of Large Technical Systems
Authors: Geels Frank W.
Published: February 2007

The transformation of existing systems is an underexposed topic in large technical systems (LTS) research. Most LTS research has focused on the emergence and stabilization of systems, ending with momentum. But how is momentum overcome, and how do transformations come about? This article presents a multilevel perspective to understand such transformations, using insights from STS and evolutionary economics. The multilevel perspective is illustrated with a longitudinal case study of the Dutch highway system (1950 to 2000).
Influences of Women’s Employment on the Gendered Division of Household Labor Over the Life Course
Authors: Cunningham Mick
Published: February 2007

Drawing on data from a panel study of White women spanning 31 years, the analyses examine the influence of women’s employment on the gendered division of household labor. Multiple dimensions of women’s employment are investigated, including accumulated employment histories, current employment status, current employment hours, and relative income. Results from fixed effect and change score models suggest that the husbands of women who accumulate more employment experience over the course of marriage perform a relatively larger amount of routine housework than the husbands of women with shorter employment histories. Women’s employment status at a given point in time also increases men’s relative participation in routine housework, and the influence of women’s employment status operates in part by increasing women’s support for egalitarian roles between spouses. Finally, women’s hours of employment and relative income are stronger predictors of housework allocation than is their current employment status.
Cultural Variations in Parental Health Beliefs, Knowledge, and Information Sources Related to Attention-Deficit/Hyperactivity Disorder
Authors: Bussing Regina , Gary Faye A. , Mills Terry L. , Garvan Cynthia Wilson
Published: February 2007

This study explores cultural variance in parental health beliefs, knowledge, and information sources related to attention-deficit/hyperactivity disorder (ADHD). Structured interviews were completed by a representative community sample of 1,615 parents, including an ADHD knowledge and perceptions survey, behavioral questionnaires, and inquiries about ADHD detection and treatment. Most parents had heard about ADHD and considered themselves knowledgeable about it but were unaware of relevant school services; those who were aware rated their knowledge levels as low. Compared to their Caucasian counterparts, African American parents reported less ADHD awareness and lower self-rated knowledge. They experienced fewer cues to action, such as receiving ADHD information from teachers or reading media accounts. Furthermore, they made more etiological attributions to sugar intake and expected less benefit from treatment. Study findings suggest a compelling need for more culturally appropriate approaches to educating African American parents about the causes and treatment options for ADHD.
The Family Structure Trajectory and Adolescent School Performance
Authors: Heard Holly E.
Published: February 2007

The question of whether family structure consequences on school achievement are the same across racial and ethnic groups is examined using longitudinal data on 10,606 teens from the National Longitudinal Study of Adolescent Health. Based on life course theory, this article uses indicators of the family structure trajectory, such as family structure duration in adolescence and the number and timing of family changes, to predict self-reported grade point average (GPA) and to examine differences in effects among non-Hispanic White, Black, and Hispanic adolescents. Results show that the negative effects of time lived with a single mother and nonparents are reduced for Black and Hispanic adolescents, whereas having a recent family change leads to a larger drop in GPA for Blacks. Racial variation in stress, social support, and school functioning explain most race differences. For minority adolescents, negative consequences of family structure are largely attenuated by race-specific social supports and educational advantages.
Gender and the Division of Household Labor in Older Couples
Authors: Hank Karsten , Jürges Hendrik
Published: February 2007

Using microdata from the 2004 Survey of Health, Ageing and Retirement in Europe (SHARE), this study takes a cross-national perspective to investigate the division of household labor among older couples (aged 50 years or more). Across nine continental European countries, the authors find considerable variation in the overall distribution of housework between partners, with more egalitarian countries in northern Europe and more traditional countries in southern Europe. A multilevel analysis shows that about half of the between-country variance in the division of housework is due to differences in older couples’ characteristics, but that there are no country-specific effects of the main microlevel explanatory variables. Finally, the authors find a significant effect of macrolevel gender inequalities on couples’ division of housework, suggesting that older couples living in more gender-egalitarian countries are more likely to exhibit an equal sharing of household labor.
Family Dynamics in Three-Generation Grandfamilies
Authors: Goodman Catherine Chase
Published: February 2007

Grandparent-headed families, called grandfamilies, are increasingly important in assisting adult children and grandchildren. This study ( N = 376) provides a qualitative analysis of statements made by grandmothers about relationships between three core family members: (a) grandmother, (b) parent, and (c) grandchild. These family members constitute an intergenerational triad, displaying a variety of relationship patterns based on emotional closeness or distance. The most common configuration in three-generation families was all-three inter-generational members emotionally close or connected, and comments about relationships reflected problem solving, communication, and emotional management. Families in which the parent was close to and linked both adjacent generations were also frequent, and comments showed a clear parenting hierarchy with grandmother as secondary. Few families had weak, disconnected relationships between all three triad members or an emotionally isolated parent: These patterns were related to low grandmother and grandchild well-being. Evaluating intergenerational relationships aids identification of at-risk grandfamilies and has implications for family interventions.
From Language Acculturation to Communication Acculturation
Authors: Ng Sik Hung
Published: February 2007

A practical problem facing minority family members is how best to acculturate to mainstream culture while maintaining their heritage language and ways of communicating. Language acculturation is well known and includes bilingualism, code-switching, and so forth. At a more subtle level, acculturation affects ways of communicating, referred to here as communication acculturation. This article serves two purposes. First, it highlights the importance of communication acculturation and illustrates this with reference to research on addressee orientation. Second, it points out that although minority families may acculturate passively by conforming to mainstream language and ways of communicating, they can actively create conversational roles that allow them to triumph over external acculturation pressures. This more active form of acculturation is illustrated in communication “brokering,” in which a family member, usually a bilingual middle-aged parent, attempts to broker a conversation between two other members who, because of language mismatch, experience difficulty engaging each other in meaningful collaborative talk.
Does the Dilution Effect Have a Conversational Basis?
Authors: Kemmelmeier Markus
Published: February 2007

The dilution effect refers to the finding that judgments are often unduly influenced by nondiagnostic information, producing regressive judgment. The hypothesis of a conversational basis of the dilution effect, advanced in a recent study by Igou and Bless, holds that the effect reflects the operation of the conversational norm of relevance. A critique and reanalysis of their data yields only weak, if any, support for this conversational explanation. Furthermore, an experiment ( n = 224) does not yield any supportive evidence, and a meta-analysis of available studies likewise supports the conclusion that the dilution effect occurs independently of the operation of conversational norms. However, consistent with a social-perceptual explanation, the experiment shows that the dilution effect occurs only for individuals high in personal need for structure. Although conversational norms do not provide the basis for the dilution effect, how they are involved in eliminating this reasoning error is discussed.
Ethnic and Racial Segregation in U.S. Metropolitan Areas, 1980-2000
Authors: Johnston Ron , Poulsen Michael , Forrest James
Published: February 2007

United States metropolitan area data for three ethnic groups—African-Americans, Asians, and Hispanics—are used to explore the dimensions of residential segregation at the 1980, 1990, and 2000 censuses at the census tract scale. Although set within Massey and Denton’s five-dimensional conceptual schema, the study was unable to replicate their identification of five empirical dimensions that correspond with the conceptual set. Instead, separate analyses for each ethnic group at each of the three censuses suggested two superdimensions: separation and location. These apply across all three groups and three censuses, although the degree of separation varies considerably among the three groups.
Reassessing Gentrification
Authors: Sullivan Daniel Monroe
Published: February 2007

Qualitative studies have focused on the proponents and the opponents to gentrification but have not provided a clear picture of the opinions of a truly representative sample of residents. This article uses probability sampling and a large sample size to examine residents in two gentrifying neighborhoods in Portland, Oregon. The results suggest that the majority of residents—including owners and renters, Whites and minorities, newcomers and longtime residents, those college educated and not—like how their neighborhood has changed and think it will improve even more in the future. However, regression analysis reveals that renters and longtime Black residents are less likely to view these changes positively.
Hands-On Learning in Tillery
Authors: Velde Beth P. , Wittman Peggy P. , Mott Vivian W.
Published: February 2007

The Tillery Experience provides a unique, cross-cultural opportunity for students to learn and practice occupational therapy skills in a rural, primarily African American community in northeastern North Carolina. This qualitative study investigates how involvement in this community-based experience affects participants. Twelve past and current students participated in a focus group. Results indicate that participants valued the hands-on learning they experienced, felt enriched as a result of the hands-on learning, and developed cultural competency as a result of their involvement in the Tillery Experience. These themes relate to theories of transformative education, transformative learning, and situated cognition. Implications for supervision and planning educational experiences are discussed.
Concepts of Motor Learning Applied to a Rehabilitation Protocol Using Biofeedback to Improve Gait in a Chronic Stroke Patient: An A-B System Study With Multiple Gait Analyses
Authors: Jonsdottir Johanna , Cattaneo Davide , Regola Alberto , Crippa Alessandro , Recalcati Mauro , Rabuffetti Marco , Ferrarin Maurizio , Casiraghi Anna
Published: February 2007

Objective. The impact of electromyographic biofeedback (EMG BFB) applied during functional gait activities and employed in accord with theories on motor learning was investigated in a chronic hemiplegic patient.

Methods. A single-subject A-B design was used. EMG BFB was applied to the triceps surae during gait. A rehabilitation program with a fading frequency of BFB application and an increasing variability in the task training was implemented. Responses to the rehabilitation program were documented via multiple quantitative gait analyses, performed during a baseline, treatment, and at follow-up 6 weeks after the end of treatment.

Results.From baseline to end of treatment, there were significant changes in ankle power at push-off, both in amplitude and timing, as well as onset of ankle power at push-off relative to heel strike of the healthy leg. There was a significant increase in gait velocity, step length of the healthy side, stride length, and stride frequency. At follow-up, changes were still significantly different from baseline and the patient had reduced the use of the cane in activities of daily living.

Conclusions. BFB appears to have been effective in promoting positive changes in gait in this pilot study. The rehabilitation protocol also appeared to be effective in promoting learning and the incorporation of trained activities into daily activities.
Musculoskeletal Adaptations in Chronic Spinal Cord Injury: Effects of Long-term Soleus Electrical Stimulation Training
Authors: Shields Richard K. , Dudley-Javoroski Shauna
Published: February 2007

Objective. The purpose of this study was to determine whether long-term electrical stimulation training of the paralyzed soleus could change this muscle’s physiological properties (torque, fatigue index, potentiation index, torque-time integral) and increase tibia bone mineral density.

Methods. Four men with chronic (>2 years) complete spinal cord injury (SCI; American Spinal Injury Association classification A) trained 1 soleus muscle using an isometric plantar flexion electrical stimulation protocol. The untrained limb served as a within-subject control. The protocol involved ~ 30 minutes of training each day, 5 days a week, for a period of 6 to 11 months. Mean compliance over 11 months of training was 91% for 3 subjects. A fourth subject achieved high compliance after only 5 months of training. Mean estimated compressive loads delivered to the tibia were ~110% of body weight. Over the 11 months of training, the muscle plantar flexion torque, fatigue index, potentiation index, and torque-time integral were evaluated periodically. Bone mineral density (dual-energy x-ray absorptiometry) was evaluated before and after the training program.

Results.The trained limb fatigue index, potentiation index, and torque-time integral showed rapid and robust training effects ( P <.05). Soleus electrical stimulation training yielded no changes to the proximal tibia bone mineral density, as measured by dual-energy x-ray absorptiometry. The subject with low compliance experienced fatigue index and torque-time integral improvements only when his compliance surpassed 80%. In contrast, his potentiation index showed adaptations even when compliance was low.

Conclusions. These findings highlight the persistent adaptive capabilities of chronically paralyzed muscle but suggest that preventing musculoskeletal adaptations after SCI may be more effective than reversing changes in the chronic condition.
Embryonic sympathoblasts transiently express TrkB in vivo and proliferate in response to brain-derived neurotrophic factor in vitro
Authors: Straub Jennifer A , Sholler Giselle L Saulnier , Nishi Rae
Published: February 2007

Background

Nerve growth factor and neurotrophin-3 are involved in the development of sympathetic neurons; however, whether brain derived neurotrophic factor also plays a role is not known. The purpose of this study was to determine whether BDNF and its receptor, TrkB, are expressed during the development of paravertebral sympathetic ganglia in vivo and to determine the effect of BDNF in vitro.

Results

As neural crest cells coalesce to form sympathetic ganglia, TrkB-positive cells are seen in both chicken and mouse embryos. In chicken embryos, TrkB-expressing cells first appear at Hamburger-Hamilton Stage (St) 27 and they co-express HNK-1, confirming that they are migrating neural crest cells. The TrkB-positive cells lack neural markers at this stage; however, they migrate with other neurally differentiating cells that are TrkA and TrkC-positive. By St. 29/30, TrkB-positive cells begin to express the neural specific markers Hu C/D and Islet-1; eventually, all TrkB positive cells commence neural differentiation. By St. 34, TrkB and TrkC staining are lost. BDNF transcript expression parallels that of TrkB. In the mouse, TrkB-positive cells surround newly formed sympathetic ganglia and a small number of TrkB positive cells that co-express tyrosine hydroxylase are seen within ganglia between E13.5-15. In cell culture, many cells from St. 29–30 chicken lumbar sympathetic ganglia express neural markers and are dividing, indicating that they are sympathoblasts. Sympathoblasts and neurons require both nerve growth factor and neurotrophin-3 for survival. BDNF increases the number of cells expressing neural markers in culture by increasing number of cells that incorporate bromodeoxyuridine. In contrast, most TrkB-positive sympathetic cells in vivo are not actively proliferating between E6–E8.

Conclusion

Developing paravertebral sympathetic ganglia in avian and murine embryos contain a subpopulation of sympathoblasts that transiently express TrkB and ultimately commence neuronal differentiation. These TrkB expressing sympathoblasts are not actively dividing in vivo; yet, when placed in vitro, will divide in response to BDNF. This suggests that the availability of BDNF in vivo fails to reach a threshold necessary to induce proliferation. We suggest that excess TrkB stimulation of sympathoblasts in vivo may lead to the genesis of neuroblastoma.
Wnt signaling induces differentiation of progenitor cells in organotypic keratinocyte cultures
Authors: Slavik Marni A , Allen-Hoffmann B Lynn , Liu Bob Y , Alexander Caroline M
Published: February 2007

Background

Interfollicular skin develops normally only when the activity of the progenitor cells in the basal layer is counterbalanced by the exit of cells into the suprabasal layers, where they differentiate and cornify to establish barrier function. Distinct stem and progenitor compartments have been demonstrated in hair follicles and sebaceous glands, but there are few data to describe the control of interfollicular progenitor cell activity. Wnt signaling has been shown to be an important growth-inducer of stem cell compartments in skin and many other tissues.

Results

Here, we test the effect of ectopic Wnt1 expression on the behavior of interfollicular progenitor cells in an organotypic culture model, and find that Wnt1 signaling inhibits their growth and promotes terminal differentiation.

Conclusion

These results are consistent with the phenotypes reported for transgenic mice engineered to have gain or loss of function of Wnt signaling in skin, which would recommend our culture model as an accurate one for molecular analysis. Since it is known that canonical ligands are expressed in skin, it is likely that this pathway normally regulates the balance of growth and differentiation, and suggests it could be important to pathogenesis.