bluuebunny/crossref_metadata_2025 huggingface dataset:
Eisenhower and Kennedy: A Comparison of Confrontations at Little Rock and Ole Miss
Authors: Stern Mark
Published: September 2005

The purpose of this study is to assess the ways in which President Dwight D. Eisenhower and John F. Kennedy reacted to the civil rights crises in Little Rock in 1957 and at Ole Miss in 1962. A side theme is to assess presidential learning by seeing whet Kennedy learned from the lessons taught by Eisenhower. Each president was reluctant to commit federal troops to enforcing civil rights, was concerned about the problems associated with federalism, and ended up feeling forced to commit troops nonetheless. The message is that despite the presidents' best intentions, troops ultimately had to be committed. Kennedy was unable to avoid the traps that Eisenhower had encountered, and the imposition of the national government on the enforcement of civil rights was firmly established.
Taking the Local: The Reagan Administration, New Federalism, and Fair Housing Implementation
Authors: Lamb Charles M. , Twombly Jim
Published: September 2005

This article explores how “New Federalism” under President Ronald W. Reagan manifested itself in the implementation of fair housing policy. We examine the Fair Housing Assistance Program (FHAP) and how it led to state and local civil rights agencies playing an increasingly vital role in implementing the Fair Housing Act of 1968. Relying on data provided by the U.S. Department of Housing and Urban Development (HUD), we show that a significant number of fair housing complaints were shifted from HUD to state and local agencies.
The Origins of New Deal Agricultural Policy: Interest Groups' Role in Policy Formation
Authors: Young James T.
Published: September 2005

In its examination of New Deal agricultural programs, this article takes issue with the pluralist, state‐centered, and class‐centered approaches which ignore the complexity of these policy programs' development and implementation as well as the role of organized interests. This over simplification is rectified through a comparison of the AAA and FSA programs, which demonstrates the primary role played in these programs' existance by organized interests both outside and within, the state.
Indian Water Settlements: The Prerequisites of Successful Negotiation
Authors: McCool Daniel
Published: September 2005

Beginning in the late 1970s, the federal government adopted a policy of negotiating, rather than litigating, conflicts over Indian water claims. In the ensuing years numerous settlements have been authorized by Congress. According to the literature on dispute resolution, successful negotiations are usually characterized by a specific set of conditions. This paper assesses the extent to which Indian water settlements are characterized by these conditions.
The Politics of Motor Fuel Taxes and Infrastructure Funds in France and the United States
Authors: Dunn James A.
Published: September 2005

The US. and France have adopted contrasting models of motor fuel tax and highway finance policy. Fuel tax revenues are dedicated to state and federal highway funds in America, keeping taxes quite low, but preventing them from contributing to the general treasury. French motor fuel taxes are higher and make up nearly 11 percent of the central government's general revenues, excluding social security contributions. French highway finance relies heavily on tolls. Pressure from the US. federal deficit has reduced the highway trust fund's ability to protect highway spending from budgetary competition. Political and procedural changes in Congress make it likely that the U.S.will move away from exclusive dedication of motor fuel taxes.
Federal Aid and Rural County Highway Spending: A Review of the 1980
Authors: Walzer Norman , Deller Steven C.
Published: September 2005

The Reagan/Bush Administrations cut back federal support for state and local governments during the 1980s, causing total real resources available to finance local roads and bridges to increase very slowly between 1977 and 1989. The effect of federal aid on spending for infrastructure has been subject to debate for many years. Some studies have indicated that federal aid is stimulative, while others report that federal aid substitutes for local resources. This article examines the effect of state and federal aid on county highway spending. The analysis demonstrates that, in 1987, federal aid was stimulative but state aid was not. In light of changes brought about by the Surface Transportation Efficiency Act of 1991 (ISTEA), we can expect federal aid to have a stronger relationship with local highway spending.
Public Assistance and Promotion of Local Rail Projects.
Authors: Walter Clyde Kenneth , Maze T. H. , Maggio Mark E. , Smadi Ayman G. , Allen Benjamin J.
Published: September 2005

In the second half of the nineteenth century, and again in the middle of the twentieth century, federal, state, and local governments were involved in large‐scale subsidizing and promoting of railroad infrastructure for economic development purposes. In the 1800s, public financial involvement centered on the expansion of railroads to develop the West. In the 1960s, 1970s, and early 1980s, public financial assistance focused on preserving rail freight services, and on restructuring the then oversized national rail network. In the 1990s and beyond, rail improvements and the need for public assistance are likely to be more incremental, with mostly local projects. Case study research was conducted on six local freight rail service projects, all of which had public sector investment. Five attributes were identified whose presence was associated with project success, or conversely, whose absence may have reduced the likelihood for project success. These success attributes should be used as an adjunct to sound economic analysis, and incorporated within future policies governing selection of local rail projects to receive public assistance.
Establishing National Priorities for Rail Transit Investments
Authors: Marshment Richard S.
Published: September 2005

The analysis assesses impacts on urban rail transit investment priorities resulting from use of different evaluation measures. To illustrate the effect of alternative evaluation methodologies, proposed fixed guideway projects from five U.S. cities are ranked according to five measures of project merit. The study concludes that the current Federal Transit Administration rail transit evaluation measure is biased against projects designed to serve long‐distance travelers and designed to improve conditions for existing transit patrons. The FTA measure may also result in inferior project selection and can be difficult to interpret in certain common situations. Recommendations are offered on ways to improve the existing evaluation process. The study identifies a potential replacement index for the current federal cost effectiveness measure.
Resources Versus Results: Comparative Performance of State Highway Systems, 1984–1990
Authors: Hartgen David T. , Krauss Russell T.
Published: September 2005

This article compares the relative performance of the U.S. and the 50 state highway systems against resources available, over the period 1984–1990. Data are collected on 13 measures of revenues, expenditures, pavement condition, congestion, bridge condition, and accidents. Statistics are normalized to control the effects of size and inflation. Each state's performance is then graded according to whether the state is making progress, holding steady, or losing ground relative to the national trends. Findings show that the U.S. highway system is in good condition and is continuing to improve: even statistics on congestion are now beginning to show improvement. Against this general improvement six states have been able to maintain or improve their highway systems with considerably less resources per mile than other states. These states are New Mexico, South Dakota, Wyoming, Mississippi, South Carolina, and Arkansas. Each of these stales seems to have a combination of geography, traffic, economic structure, and fiscal capability that results in particularly cost‐effective highway systems. The findings suggest that simplistic explanations of performance based on location, urban/rural distinctions, weather, climate, or taxes are inadequate; more research is needed to explain the causes of these differences.
The Attitudes of State Legislators and State Medicaid Policies Related to AIDS
Authors: Buchanan Robert J. , Ohsfeldt Robert L.
Published: September 2005

As the Medicaid programs become increasingly important payers of AIDS‐related care, state governments will face difficult policy choices in allocating limited Medicaid resources among many competing health needs. The state legislatures will play a critical role in these allocation decisions. This research presents the results of an analysis of attitudes concerning Medicaid coverage of AIDS‐related care among state legislators serving on health‐related committees in all 50 states. The model employed includes characteristics of the state legislators, their districts, and their states to explain the legislators' allocation choices and attitudes relating to Medicaid coverage of AIDS‐related care. The relationship of these factors to the actualization of AIDS‐related state policy also is examined. The model identified political ideology, party affiliation, and sex of the state legislator as the most important predictors of attitudes about AIDS‐related Medicaid policies. AIDS prevalence, constituency characteristics, and legislator attitudes are the most important predictors of actual state policies.
Environment/Equity: Tensions in North American Politics
Authors: Paehlke Robert , Vaillancourt Rosenau Pauline
Published: September 2005

Throughout the past 30 years there has been a perception of tension between social equity objectives and the agenda of environmental politics. This tension has arisen in many forms and arenas: on a social class basis, on a gender basis, and on a racial basis; regarding jobs, regarding health, and regarding competition for governmental funding. At the base, however, many of the tensions are as much perceived as real. There is more basis far common purpose between these several social movements and objectives than is ordinarily perceived.
George Bush and Executive Branch Domestic Policymaking Competence
Authors: Williams Walter
Published: September 2005

This article critiques the George Bush domestic policymaking process and argues that Bush had the second‐lowest level of policy competence among postwar presidents, ranking above only Ronald Reagan. Although not overtly antianalytic like Reagan, Bush gave little thought and effort to restoring the badly damaged executive branch domestic policymaking process. The article closes with suggestions about the steps needed for, and the difficulties in establishing, a strong White House policymaking process that generates fruitful interaction among key policy advocates over time and that establishes sufficient Executive Office of the President (EOP) capacity to monitor the implementation and management of presidential policies.
Overview of the Disability Movement: History, Legislative Record, and Political Implications
Authors: Pfeiffer David
Published: September 2005

This article presents a brief history and legislative record of the disability movement, along with their political implications. Beginning with the mid‐nineteenth century efforts of Samuel Gridley Howe, the history of disability policy is reviewed. The impact of the field of eugenics is assessed. Notable achievements of the disability movement over the last two decades are presented, culminating in the Americans with Disabilities Act. The basic paradigm of disability policy is presented. The political and policy implications facing the disability movement are discussed.
Holistic Policymaking: “Neo‐Liberalism” as Illustrated by the Women's and Disability Rights Movements
Authors: Watson Sara D.
Published: September 2005

The past several decades have seen the rise of two movements, the disability rights movement and the women's movement, with parallel concerns, histories, organizational issues, and other attributes. This article examines the philosophies of the two movements and their significance for the policymaking process. For example, both have struggled with the issues of difference versus equality in determining public policy; both stress the importance of considering problems to reside not in personal characteristics but in interactions with the environment. The article traces these and other similarities in ways of looking at policy problems between the women's movement and the disability movement, examines how these similarities reveal a fundamentally different view of policymaking, compares this philosophy with basic tenets of the Clinton administration, as expressed by key policymakers, and discusses what policy would look like if these changes occurred.
Access to the Information Age: Fundamental Decisions in Telecommunications Policy
Authors: Bowe Frank G.
Published: September 2005

As federal and state budget sheets show more red than black ink, the private sector is delivering more social services and even protecting rights. The experience of disability rights leaders during the past five years shows that the private sector will accept such obligations as long as the burden is evenly distributed throughout an industry. They will balk if it is not. The task of ensuring access and fairness for people with disabilities in an industry where equal allocation of social responsibility is difficult is illustrated by the continuing effort of disability rights leaders for accessibility to Information Age telecommunications products and services. The effort also highlights a recurring theme in public policy: Does equity mean that all Americans pay a little more so that those with disabilities gain full access, or does it mean that overall rates are kept low while those with special needs use adaptive devices? Each point of view was illustrated in the telecommunications policy debate of the 102nd Congress‐and likely will shape that of the 103rd Congress as well.
The Americans with Disabilities Act: will it Make a Difference?
Authors: Johnson William G. , Baldwin Marjorie
Published: September 2005

This article summarizes the research on labor market discrimination against persons with disabilities and discusses the implications of that research for the probable success of the Americans with Disabilities Act (ADA). The research shows that discrimination reduces the wages of men and women with disabilities relative to nondisabied men and women. The size of discriminatory wage differentials varies with the intensity of prejudice toward particular impairments, suggesting that prejudice is an important problem. Employment rates for persons with disabilities are also substantially lower than employment rates for nondisabied persons, but it is unclear to what extent the lower employment rates are attributable to discrimination. The most important provision of the ADA with respect to employment is its requirement for “reasonable accommodation.” The success of the ADA in improving employment rates for disabled persons will be determined by how employers evaluate the costs of accommodating workers with disabilities relative to the costs of noncompliance.
Democracy and the Policy Sciences
Authors: DeLeon Peter
Published: September 2005

The policy sciences approach has recently came under sustained criticism for being insensitive to the values and preferences of the ordinary citizen. This paper attempts to address these problems by outlining a post‐positivist approach, drawing upon the works of Jürgen Habermas. The paper proposes a “participatory policy analysis” that utilizes a sampling of affected citizens to create a “policy forum” to inform the policymaker of citizens' positions on important policy issues.
The Politics of HDTV in the United States
Authors: Hart Jeffrey A.
Published: September 2005

Policies adopted by the United States government between 1987 and 1993 regarding high definition television (HDTV) were made primarily by the Federal Communications Commission (FCC). A brief effort by members of Congress and their bureaucratic and industrial allies to link HDTV to broader industrial policies was thwarted by the George Bush Administration between 1988 and 1990. The FCC's policies with respect to simulcasting and digital signals reflected the concern of that agency to protect the interests of consumers, broadcasters, and electronics manufacturers. The first two interests traditionally were protected by the FCC, whereas the protection of electronics was somewhat unusual and was influenced by perceptions of declining United States competitiveness. In addition, United States policymaking in this area depended strongly on the framing effect of policies adopted in Japan and Western Europe.
Public Policy and Emerging Sources of Technology and Technical Information Available to Industry
Authors: Roessner J. David , Wise Anne
Published: September 2005

As technologies grow in complexity, firms often target their internal R&D resources on core competencies and utilize outside sources for supporting knowledge and technology. Where do firms turn to find such resources? This paper reports the perceptions of technology transfer managers in United States manufacturing firms toward federal and university labs and identifies the types of farms that are better positioned to utilize externally available technological resources. Based on replies from research‐intensive companies within the United States, the authors find that larger firms with high research and development (R&D) budgets tend to ascribe greater significance to external sources than do smaller ones. Also, companies spending over $500 million in R&D rank universities the most significant external source of knowledge, followed by V S.‐based firms, and then foreign firms.
Sizing Up State Policy Innovation Research
Authors: Berry Frances Stokes
Published: September 2005

In the literature on state policy innovation, there are three major explanations for what causes a government to adopt a new policy. One is the internal determinants model, which posits that the main factors leading a state to innovate are internal political, social and economic characteristics of the stale. The other two are diffusion models—the regional diffusion model, and the national interaction model—which see slate policy adoptions as emulations of earlier adoptions by other states. Each of the three models has been associated with a distinct strategy for empirical testing. The regional diffusion model has been tested with factor analysis, the national interaction model with time‐series regression, and the internal determinants model with cross‐sectional regression. In this paper, I explore the ability of these “single‐explanation” methodologies to detect the true innovation process underlying stale policy adoptions, by applying these methodologies to data generated from simulated innovation processes with known characteristics. I find that the methodologies often yield incorrect conclusions about the character of innovation. I conclude by presenting an agenda for refining a superior alternative methodology: the event history analysis approach to state policy innovation research introduced by Berry and Berry (1990).
Reconsidering the Tribal‐State Compact Process
Authors: Wilkins David E.
Published: September 2005

This essay evaluates the tribal‐state compact process, as one of several alternative, nonadversarial processes, warranting attention. It argues that, because of its binding character and relatively low cost (in contrast to litigation), and because it is based in the idea of tribes and states exhibiting mutual respect, the compact process is an advanced version of negotiation and bargaining that tribes and states should consider where appropriate.
Could Privatization Increase the Efficiency of Tax Administration in Less‐Developed Countries?
Authors: Kiser Edgar , Baker Kathryn
Published: September 2005

In spite of the fact that state tax collection systems in less‐developed countries generally are characterized by high levels of tax evasion and official corruption, little experimentation with privatized tax collection has occurred in these countries. This is due in part to: (1) The fact that the literature on privatization has not focused on tax collection, and (2) the existence of prevalent misconceptions regarding the effects of privatized tax collection in earlier periods. This paper uses agency theory and privatization research to discover the conditions under which privatized tax collection may be an efficient alternative to state tax collection, and to show that these conditions are present in many less‐developed countries.
Is There a National Policy For Children and Youth With Serious Emotional Disturbance?
Authors: Koyanagi Chris
Published: September 2005

This article examines the status of a national mental health policy for children in need of mental health services. The need for systems planning and services integration involving multiple agencies is presented. The different programs of the major governmental agencies involved in the delivery of services to children are reviewed, as are the range of services provided. This article demonstrates the fragmentation and duplication that is endemic in all aspects of mental health, and that consequently makes policy implementation exceedingly difficult.
Policy Influence and Policy Responsiveness in State Pollution Control
Authors: Ringquist Evan J.
Published: September 2005

This article develops an integrated theory of state policy influence and responsiveness, then operationalizes this theory to account for variations in the strength and scope of state water pollution control and hazardous waste management programs. The analysis finds that economic, ideological, interest group, and political system characteristics act in concert to affect state policymaking, and that the influences behind policymaking vary systematically and predictably across policy areas within environmental protection.
Paved With Political Intentions: The Impact of Structure on the National Park Services of Canada and the United States
Authors: Lowry William R.
Published: September 2005

The structural allocation of decisionmaking power between political authorities and career civil servants influences agency policy behavior. I propose and examine this argument in the context of the national park service agencies of Canada and the United States. Centralization of power to political authorities increases agency attention to electoral concerns such as visitor service. Empowerment of careerists enhances attention to long‐term agency goals such as preservation of natural resources.
The Search for Policy Coordination: Ministerial and Bureaucratic Perceptions of Agency Amalgamations in a Federal Parliamentary System
Authors: Craswell Emma , Davis Glyn
Published: September 2005

The imperative to coordinate is strong, but the means remain contentious. One approach is to amalgamate agencies into a few large organizations, the other to encourage a diversity of policy options. Drawing on the federal amalgamations of departments in Australia since 1987, this paper reports that senior bureaucrats find more policy coordination benefits than costs from working in larger structures, while ministers report a loss of options and a risk of information overload.
Organizing From Diversity in the Name of Community: Lessons From the Disability Civil Rights Movement
Authors: McGuire Jean Flatley
Published: September 2005

The recent passage of the Americans with Disabilities Act and other pieces of legislation affecting the disability community and other civil rights communities suggests a level of cohesion within the disability movement that blurs the reality and the power of the tensions which did and do exist. Examining the struggles to maintain an effective, cohesive entity provides an opportunity to explore the complexity of the disability movement as well as lessons for policy and program planning and for community organizing.
The Implications of Parenting Standards in Child Protection: A Paradox in Disability Policy
Authors: Matava Marie
Published: September 2005

Contemporary parenting standards in the field of child protection produce a paradox in disability policy. Focusing on the protections necessary for child safety, child protection workers are apt stereotypically to discount the abilities of parents with disabilities to raise their children. This situation runs a wide spectrum. It includes parents fully capable of parenting with no outside assistance who are nevertheless denied their children on the basis of completely baseless stereotypical assumptions. It includes parents who are mentally fully capable of parenting, but who are denied the necessary personal assistance services to perform the physical tasks of child care. This article, however, focuses on yet another situation: parents with mental, emotional, or cognitive disabilities who, without assistance to perform the cognitive tasks necessary for safely raising children, could neglect their children. It discusses this situation in light of the Americans with Disabilities Act and various state laws that protect the civil rights of persons with disabilities.
HPA axis normalization, estimated by DEX/CRH test, but less alteration on cerebral glucose metabolism in depressed patients receiving ECT after medication treatment failures
Authors: Yuuki N. , Ida I. , Oshima A. , Kumano H. , Takahashi K. , Fukuda M. , Oriuchi N. , Endo K. , Matsuda H. , Mikuni M.
Published: September 2005

Objective:  To examine the clinical effects of electroconvulsive therapy (ECT) on depressed patients with medication treatment failures, we investigated the alterations in hypothalamic‐pituitary‐adrenocortical (HPA) function and regional cerebral metabolism rate of glucose (rCMRGlu) after ECT in these patients.

Method:  Before and after ECT, the combined dexamethasone/corticotrophin‐releasing hormone (DEX/CRH) test was administered to seven patients who were referred for ECT. In the same patients, 18F‐fluorodeoxyglucose positron emission tomography (18F‐FDG PET) was also assessed.

Results:  Cortisol response in the DEX/CRH test significantly decreased after a successful ECT. A significant hypometabolism in various frontal regions and hypermetabolism in the parietal regions of these patients when compared with controls remained after ECT.

Conclusion:  Depressed patients who failed trials of antidepressant medication showed a remission with ECT that was accompanied by resolution of HPA dysregulation. However, measures of cerebral brain metabolism did not resolve.
Incision design in implant dentistry based on vascularization of the mucosa
Authors: Kleinheinz Johannes , Büchter André , Kruse‐Lösler Birgit , Weingart Dieter , Joos Ulrich
Published: September 2005

Objectives: The delivery of an adequate amount of blood to the tissue capillaries for normal functioning of the organ is the primary purpose of the vascular system. Preserving the viability of the soft tissue segment depends on the soft tissue incision being properly designed in order to prevent impairment of the circulation. A knowledge of the course of the vessels as well as of their supply area are crucial to the decision of the incision. The aim of this study was to visualize the course of the arteries using different techniques, to perform macroscopic‐ and microscopic analyses, and to develop recommendations for incisions in implant dentistry.

Material and methods: The vascular systems of seven edentulous human cadavers were flushed out and filled with either red‐colored rubber bond or Indian ink and formalin mixture. After fixation a macroscopic preparation was performed to reveal the course, distribution and supply area of the major vessels. In the area of the edentulous alveolar ridge specimens of the mucosa were taken and analyzed microscopically.

Results: The analyses revealed the major features of mucosal vascularization. The main course of the supplying arteries is from posterior to anterior, main vessels run parallel to the alveolar ridge in the vestibulum and the crestal area of the edentulous alveolar ridge is covered by a avascular zone with no anastomoses crossing the alveolar ridge.

Conclusion: The results suggest midline incisions on the alveolar ridge, marginal incisions in dentated areas, releasing incisions only at the anterior border of the entire incision line, and avoidance of incisions crossing the alveolar ridge.
Sinus floor elevation via hydraulic detachment and elevation of the Schneiderian membrane
Authors: Vitkov Ljubomir , Gellrich Nils‐Claudius , Hannig Matthias
Published: September 2005

Objectives: Minor sinus floor elevation is a method with relatively high predictability but is technically demanding. Improvement of the technique and increase in the predictability are desirable.

Material and methods: A clinical protocol for minor sinus floor elevation with SLA®‐ITI® (large grit acid‐etched implants with diameter of 4.8 mm) is described. Using trephine instead of spiral burrs enables the harvesting of autogenous grafts from the implant socket and guarantees a perfect implant socket. The latter is necessary for optimal implant anchoring and for the hydraulic seal between socket and the osteotome. The whole allows a hydraulic detachment of the Schneiderian membrane, where the blood cushion gradually detaches and elevates the membrane, preventing its contact with the graft.

Results: Eight patients were successfully treated with the method described above. No membrane perforation occurred and an uneventful healing was observed in all patients. All implants were loaded prosthodontically 3 months after the implantation.

Conclusions: The clinical protocol presented provides high predictability in clinical outcome, together with extremely low morbidity and shortened surgery.
Cortical regions associated with autonomic cardiovascular regulation during lower body negative pressure in humans
Authors: Kimmerly Derek S. , O'Leary Deborah D. , Menon Ravi S. , Gati Joseph S. , Shoemaker J. Kevin
Published: September 2005

The purpose of the present study was to determine the cortical structures involved with integrated baroreceptor‐mediated modulation of autonomic cardiovascular function in conscious humans independent of changes in arterial blood pressure. We assessed the brain regions associated with lower body negative pressure (LBNP)‐induced baroreflex control using functional magnetic resonance imaging with blood oxygen level‐dependent (BOLD) contrast in eight healthy male volunteer subjects. The levels of LBNP administered were 5, 15 and 35 mmHg. Heart rate (HR; representing the cardiovascular response) and LBNP (representing the baroreceptor activation level) were simultaneously monitored during the scanning period. In addition, estimated central venous pressure (CVP), arterial blood pressure (ABP) and muscle sympathetic nerve activity were recorded on a separate session. Random effects analyses (SPM2) were used to evaluate significant (P< 0.05) BOLD signal changes that correlated separately with both LBNP and HR (15‐ and 35‐mmHgversus5‐mmHg LBNP). Compared to baseline, steady‐state LBNP at 15 and 35 mmHg decreased CVP (from 7 ± 1 to 5 ± 1 and 4 ± 1 mmHg, respectively) and increased MSNA (from 12 ± 1 to 23 ± 3 and 36 ± 4 bursts min−1, respectively, bothP< 0.05versusbaseline). Furthermore, steady‐state LBNP elevated HR from 54 ± 2 beats min−1at baseline to 64 ± 2 beats min−1at 35‐mmHg suction. Both mean arterial and pulse pressure were not different between rest and any level of LBNP. Cortical regions demonstrating increased activity that correlated with higher HR and greater LBNP included the right superior posterior insula, frontoparietal cortex and the left cerebellum. Conversely, using the identical statistical paradigm, bilateral anterior insular cortices, the right anterior cingulate, orbitofrontal cortex, amygdala, midbrain and mediodorsal nucleus of the thalamus showed decreased neural activation. These data corroborate previous investigations highlighting the involved roles of the insula, anterior cingulate cortex and amygdala in central autonomic cardiovascular control. In addition, we have provided the first evidence for the identification of the cortical network involved specifically with baroreflex‐mediated autonomic cardiovascular function in conscious humans.
A new quantitative (two‐photon extracellular polar‐tracer imaging‐based quantification (TEPIQ)) analysis for diameters of exocytic vesicles and its application to mouse pancreatic islets
Authors: Kasai Haruo , Hatakeyama Hiroyasu , Kishimoto Takuya , Liu Ting‐Ting , Nemoto Tomomi , Takahashi Noriko
Published: September 2005

We have developed an imaging approach to estimate the diameter of exocytic vesicles that are smaller than the resolution of an optical microscope and present within intact tissue. This approach is based on two‐photon excitation imaging of polar tracers in the extracellular medium, is designated TEPIQ (two‐photon extracellular polar‐tracer imaging‐based quantification), and has three variants. TEPIQ analysis of ΔV measures vesicle volume with a fluid‐phase tracer, sulforhodamine B (SRB). TEPIQ analysis of ΔS determines vesicle surface area with a polar membrane tracer, FM1‐43. TEPIQ analysis of ΔV/ΔS estimates vesicle diameter from the SRB/FM1‐43 fluorescence ratio. TEPIQ analysis is insensitive to microscope settings because the same setup is used for calibration and actual experiments. We tested the validity of TEPIQ with glucose‐induced exocytosis from beta‐cells within pancreatic islets. The three TEPIQ variants yielded estimates for the mean diameter of exocytic vesicles of between 340 and 390 nm, consistent with the size of insulin granules. TEPIQ analysis relies on the combination of two‐photon excitation imaging, the narrow intercellular spaces of intact tissue, and the presence of diffusible polar tracers in the extracellular medium. It allows quantitative imaging of exocytosis within secretory organs, yielding estimates of vesicle diameter with nanometer resolution.
Exocytosis and endocytosis of small vesicles in PC12 cells studied with TEPIQ (two‐photon extracellular polar‐tracer imaging‐based quantification) analysis
Authors: Liu Ting‐Ting , Kishimoto Takuya , Hatakeyama Hiroyasu , Nemoto Tomomi , Takahashi Noriko , Kasai Haruo
Published: September 2005

We investigated exocytosis of PC12 cells using two‐photon excitation imaging and extracellular polar tracers (TEP imaging) in the lateral membranes not facing the glass‐cover slip. Upon photolysis of a caged Ca2+ compound, TEP imaging with FM1‐43 (a polar membrane tracer) detected massive exocytosis of vesicles with a time constant of about 1 s. TEPIQ (two‐photon extracellular polar‐tracer imaging‐based quantification) analysis revealed that the diameter of vesicles was small (55 nm). Extensive exocytosis of small vesicles (SVs) was shown to be mediated by the transient opening of a fusion pore with a diameter less than about 1.6 nm, and to be followed by direct (‘kiss‐and‐run’) endocytosis and translocation of the endocytic vesicles (EVs) deep into the cytoplasm. These processes were unaffected by GTP‐γ‐S. In contrast, constitutive endocytic vesicles exhibited a diameter of 90 nm, took up molecules with a diameter of > 12 nm, and their formation was blocked by GTP‐γ‐S. Electron‐microscopic investigation with photoconversion of diaminobenzidine using FM1‐43 confirmed an abundance of EVs with a diameter of 54 nm in stimulated cells. They rapidly translocated into the cytosol, and fused with endosomal organelles. The number of SV exocytosis events vastly exceeded the number of SVs morphologically docked at the plasma membrane. Simultaneous capacitance and FM1‐43 measurements indicated that TEP imaging detected most SV exocytosis, and the fusion pore was closed within 2 s. Thus, we have, for the first time, directly visualized massive exocytosis of small vesicles in a non‐synaptic preparation, and have revealed their fusion‐pore mediated exocytosis and endocytosis.
Ca2+‐independent activation of BKCa channels at negative potentials in mammalian inner hair cells
Authors: Thurm Henrike , Fakler Bernd , Oliver Dominik
Published: September 2005

The defining characteristic of large‐conductance Ca2+‐ and voltage‐activated K+ channels (BKCa) is their allosteric activation by two distinct stimuli, membrane depolarization and cytosolic Ca2+ ions. In this allosteric gating, increasing cytosolic Ca2+ concentration ([Ca2+]i) shifts the depolarization required for channel opening into the physiological voltage range. In fact, according to present knowledge, elevation of [Ca2+]i to micromolar levels is the only means to activate BKCa at membrane potentials below 0 mV. We recorded BKCa‐mediated currents from auditory inner hair cells (IHCs) in acutely isolated organs of Corti using the patch‐clamp technique in whole‐cell and excised patch configuration. In inside‐out and outside‐out patches, activation of BKCa channels from IHCs showed the prototypic sensitivity to increased [Ca2+]i. However, channel activation at 0 [Ca2+]i occurred at unusually negative potentials (half‐maximal activation (Vh) around 0 mV), indicating that a large fraction of the channels can be activated at physiological voltages without elevated [Ca2+]i. In intact IHCs, the activation curve of BKCa currents recorded in whole‐cell configuration exhibited a Vh of −42 mV together with a high voltage dependence (slope factor of 10 mV) and submillisecond onset of current. Surprisingly, this activation was independent of changes in local [Ca2+]i as shown by experiments that interfered with Ca2+ influx through voltage‐gated Ca2+ (Cav) channels, release of Ca2+ from internal stores, or intracellular buffer capacity. This behaviour is not due to β‐subunits of BKCa (BKβ), as genetic inactivation of the β‐subunit expressed in IHCs, KCNMB1, did not affect BKCa gating. We conclude that the BKCa channel protein in IHCs may be modified in order to rapidly activate and deactivate at resting [Ca2+]i. Our results suggest that BKCa may function as a purely voltage‐gated K+ channel with exceptionally rapid activation kinetics, challenging the view that both increased cytosolic Ca2+ and depolarization are generally required for activation of BKCa.
The effect of caffeine on glucose kinetics in humans – influence of adrenaline
Authors: Battram Danielle S. , Graham Terry E. , Richter Erik A. , Dela Flemming
Published: September 2005

While caffeine impedes insulin‐mediated glucose disposal in humans, its effect on endo‐genous glucose production (EGP) remains unknown. In addition, the mechanism involved in these effects is unclear, but may be due to the accompanying increase in adrenaline concentration. We studied the effect of caffeine on EGP and glucose infusion rates (GIR), and whether or not adrenaline can account for all of caffeine's effects. Subjects completed three isoglycaemic–hyperinsulinaemic clamps (with 3‐[3H]glucose infusion) 30 min after ingesting: (1) placebo capsules (n= 12); (2) caffeine capsules (5 mg kg−1) (n= 12); and either (3) placebo plus a high‐dose adrenaline infusion (HAdr; adrenaline concentration, 1.2 nm; n= 8) or (4) placebo plus a low‐dose adrenaline infusion (LAdr; adrenaline concentration, 0.75 nm; n= 6). With caffeine, adrenaline increased to 0.6 nm but no effect on EGP was observed. While caffeine and HAdr decreased GIR by 13 (P < 0.05) and 34% (P < 0.05) versus the placebo, respectively, LAdr did not result in a significant reduction (5%) in GIR versus the placebo. Due to the fact that both caffeine and LAdr resulted in similar adrenaline concentrations, but resulted in different decreases in GIR, it is concluded that adrenaline alone does not account for the effects of caffeine and additional mechanisms must be involved.
Low Cycle Fatigue Testing of Ball Grid Array Solder Joints under Mixed-Mode Loading Conditions
Authors: Park Tae-Sang , Lee Soon-Bok
Published: September 2005

To give a proper and accurate estimation of the fatigue life of ball grid array (BGA) solder joints, a mechanical fatigue test method under mixed-mode loading is proposed. Experiments were conducted with 63Sn∕37Pb and Sn∕3.5Ag∕0.75Cu solder joints in room temperature. The mechanical low cycle fatigue tests were performed under several loading angles. The loading angle is controlled by several grips which have specific surface angle to the loading direction. Constant displacement controlled tests are performed using a micro-mechanical test apparatus. It was found that the normal deformation significantly affects the fatigue life of the solder joint. Throughout the whole test conditions at room temperature, Sn∕3.5Ag∕0.75Cu solder alloy had longer fatigue life than 63Sn∕37Pb alloy. Failure patterns of the fatigue tests were observed and discussed. A morrow energy model was examined and found to be a proper low cycle fatigue model for solder joints under mixed mode loading condition.
Interfacial Thermal Stresses in Trilayer Assemblies
Authors: Ghorbani H. R. , Spelt J. K.
Published: September 2005

A two-dimensional model has been developed for the interfacial thermal stresses in short and long trilayer assemblies under both plane stress and plane strain conditions. Interfacial stresses are approximated using a combination of exact elasticity solutions and elementary strength of materials theories. Governing differential equations are linearized through a finite difference discretization procedure. The conditions of zero shear stress at the free edges and self-equilibrated peel stresses are satisfied. The approach is mathematically straightforward, can be extended to include inelastic behavior, and can be adapted to problems involving external loads and a variety of geometries. The results have been compared to available data in the literature and finite element analysis.
Analyses of Convection Heat Transfer From Discrete Heat Sources in a Vertical Rectangular Channel
Authors: Bhowmik H. , Tso C. P. , Tou K. W.
Published: September 2005

Steady-state experiments are performed to study the convection heat transfer from four in-line simulated chips in a vertical rectangular channel using water as the working fluid. The experimental data cover a wide range for laminar flow under natural, mixed, and forced convection conditions with the Reynolds number based on the channel hydraulic diameter ranging from 40 to 2220 and on the heat source length ranging from 50 to 2775. The heat flux ranges from 0.1W∕cm2to0.6W∕cm2. The effects of heat flux, flow rates, and chip number are investigated and results indicate that the Nusselt number is strongly affected by the Reynolds number. To develop empirical correlations, the appropriate value of the exponent n of ReD is determined to collapse all the lines into a single line to show the independence of heat flux. Based on experimental results, the empirical correlations are developed for relations using Nuℓ, ReD, and GrD. The results are compared to predictions from a three-dimensional numerical simulation, and a numerical correlation is also developed.
Characterization of the Solder Paste Release From Small Stencil Apertures in the Stencil Printing Process
Authors: Aravamudhan Srinivasa , Santos Daryl , Pham-Van-Diep Gerald , Andres Frank
Published: September 2005

Stencil printing is a critical first step in surface mount assembly. However, its robustness can be called into question because of the fact that about 50% or more of the defects found in the assembly of printed circuit boards (PCBs) are attributed to stencil printing 1. Manufacturing techniques for the assembly of certain flip chips, chip scale packages, 0201s, and fine pitch ball grid arrays are testing the limits of current stencil printing capabilities. This paper focuses on understanding the release of solder paste from the stencil, based on experimental and modeling approaches. The primary goal of the study is to characterize the performance of various aperture sizes and geometries based on release efficiencies and to compare them to predictions. The resulting model validation helps us better understand the print process for small features and offers options for increasing print yields. The study is divided into two phases. The first phase examines the release performance of various solder pastes from a variety of aperture sizes and geometries. The focus of this study is a comparison of square versus circular apertures when the nominal volume of paste to be deposited is kept constant. The second phase consists of developing a model that predicts paste-release efficiencies from small apertures and validating the model with experimental results.
Solder Joint Shape Prediction Using a Modified Perzyna Viscoplastic Model
Authors: Ahmad Mudasir , Hubbard Ken , Hu Mason
Published: September 2005

Ball grid array solder joint reliability is known to be dependent on the shape of solder joints after reflow. To ensure good solder joint formation and prevent solder bridging, it is critical to understand the amount of paste volume needed during assembly and reflow. The final shape of the solder joint is a function of surface tension, wetting area, gravity, and applied forces. In this paper, a new methodology to simulate solder joint shape is presented. Large deformation viscoplastic finite element analysis is used to simulate incompressible fluid flow. A numerical model for surface tension is outlined and validated with closed-form solutions. The results of the numerical model are compared to other known solder joint shape prediction methods. The effects of package weight, coplanarity, warpage, paste volume, pad misregistration, and joint construction on solder joint shape are then analyzed. Recommendations are provided on ways to maximize standoff height and avoid bridging. Finally, the formation of leadless solder joints is studied and compared to experimental data.
Three-Dimensional Paddle Shift Modeling for IC Packaging
Authors: Pei Chien-Chang , Hwang Sheng-Jye
Published: September 2005

The plastic packaging process for integrated circuits is subject to several fabrication defects. For packages containing leadframes, three major defects may occur in the molding process alone, namely, incomplete filling and void formation, wire sweep, and paddle shift. Paddle shift is the deflection of the leadframe pad and die. Excessive paddle shift reduces the encapsulation protection for the components and may result in failures due to excessive wire sweep. Computer-aided analysis is one of the tools that could be used to simulate and predict the occurrence of such molding-process-induced defects, even prior to the commencement of mass production of a component. This paper presents a methodology for computational modeling and prediction of paddle shift during the molding process. The methodology is based on modeling the flow of the polymer melt around the leadframe and paddle during the filling process, and extracting the pressure loading induced by the flow on the paddle. The pressure loading at different times during the filling process is then supplied to a three-dimensional, static, structural analysis module to determine the corresponding paddle deflections at those times. The paper outlines the procedures used to define the relevant geometries and to generate the meshes in the “fluid” and “structural” subdomains, and to ensure the compatibility of these meshes for the transfer of pressure loadings. Results are shown for a full paddle shift simulation. The effect on the overall model performance of different element types for the mold-filling analysis and the structural analysis is also investigated and discussed. In order to obtain more accurate results and in a shorter computational time for the combined (fluid and structural) paddle shift analysis, it was found that higher-order elements, such as hexahedra or prisms, are more suitable than tetrahedra.