bluuebunny/crossref_metadata_2025_split huggingface dataset:
Pro‐ and retrogradeP–Tevolution of granulites of the Beit Bridge Complex (Limpopo Belt, South Africa): constraints from quantitative phase diagrams and geotectonic implications
Authors: Zeh A. , Klemd R. , Buhlmann S. , Barton J. M. 
Published: February 2004

AbstractInterpretations based on quantitative phase diagrams in the system CaO–Na2O–K2O–TiO2–MnO–FeO–MgO–Al2O3–SiO2–H2O indicate that mineral assemblages, zonations and microstructures observed in migmatitic rocks from the Beit Bridge Complex (Messina area, Limpopo Belt) formed along a clockwiseP–Tpath. That path displays a progradeP–Tincrease from 600 °C/7.0 kbar to 780 °C/9–10 kbar (pressure peak) and 820 °C/8 kbar (thermal peak), followed by aP–Tdecrease to 600 °C/4 kbar. The data used to construct theP–Tpath were derived from three samples of migmatitic gneiss from a restricted area, each of which has a distinct bulk composition: (1) a K, Al‐rich garnet–biotite–cordierite–sillimanite–K‐feldspar–plagioclase–quartz–graphite gneiss (2) a K‐poor, Al‐rich garnet–biotite–staurolite–cordierite–kyanite–sillimanite–plagioclase–quartz–rutile gneiss, and (3) a K, Al‐poor, Fe‐rich garnet–orthopyroxene–biotite–chlorite–plagioclase–quartz–rutile–ilmenite gneiss. Preservation of continuous prograde garnet growth zonation demonstrates that the pro‐ and retrogradeP–Tevolution of the gneisses must have been rapid, occurring during a single orogenic cycle. These petrological findings in combination with existing geochronological and structural data show that granulite facies metamorphism of the Beit Bridge metasedimentary rocks resulted from an orogenic event during the Palaeoproterozoic (c. 2.0 Ga), caused by oblique collision between the Kaapvaal and Zimbabwe Cratons. Abbreviations followKretz (1983).
Risk factors for HCV infection among blood donors confirmed to be positive for the presence of HCV RNA and not reactive for the presence of anti‐HCV
Authors: Orton S.L. , Stramer S.L. , Dodd R.Y. , Alter M.J. 
Published: February 2004

BACKGROUND: In 1999, NAT of blood donations was implemented to detect “window‐period” infections. Blood donors who have confirmed NAT results positive for the presence of HCV in the absence of anti‐HCV are likely to have been recently infected. Of over 26.8 million donations tested between March 3, 1999, and March 31, 2003, 810 were HCV‐reactive by NAT. A subset of these donors was assessed for recent exposure risk.STUDY DESIGN AND METHODS: All anti‐HCV– blood donors with reactive, unconfirmed HCV NAT results were invited to participate in a study that included an extensive demographic and risk questionnaire. Confirmed HCV+ cases were compared to HCV– (falsely positive) controls for histories of potential risk factors during the 6 months before donation.RESULTS: Recent injection drug use (IDU) was independently associated with HCV infection (29.2% vs. 0% of cases vs. controls, p < 0.001). In addition, likely sources were identified for three other cases (4.6%), including occupational exposure, sexual contact with an HCV‐infected partner (who was an IDU), and perinatal exposure, none of which was known to the donors at the time of donation. Incarceration was independently associated with HCV infection among the group not reporting IDU and after removal of the three donors with likely sources of risk (14.6% vs. 1.3% of cases vs. controls, p < 0.001).CONCLUSIONS: A likely risk, primarily IDU, was found for 43 percent of HCV+ donors whose infections were identified solely by NAT. Because the maximum efficiency of the donor history questions may have been reached, NAT will continue to be an important measure to interdict recently infected blood donors.
Retention of cellular properties of PBPCs following liquid storage and cryopreservation
Authors: Moroff Gary , Seetharaman Shalini , Kurtz James W. , Greco Nicholas J. , Mullen Michael D. , Lane Thomas A. , Law Ping 
Published: February 2004

BACKGROUND: G–CSF‐mobilized PBPCs are routinely cryopreserved within 24 hours of collection. The ability to hold PBPCs for extended time would offer increased flexibility for patients and hospitals. Retention of PBPC properties following overnight shipping, extended liquid storage at 1 to 6°C, and cryopreservation was evaluated.STUDY DESIGN AND METHODS: PBPCs were stored in liquid at 1 to 6°C up to 3 days, with and without shipping, and then cryopreserved in HES (6%), DMSO (5%), and HSA (4%). Thawed samples were assayed after two procedures, on dilution and after dilution and washing. Nucleated cells, viability, CD34+ cell number, committed progenitor colonies, and long‐term culture‐initiating cells were measured.RESULTS: CD34+ cell number, committed colony‐forming cells, and long‐term culture‐initiating cells were essentially maintained when samples were stored in liquid for 1, 2, or 3 days before cryopreservation or after thawing and dilution. Nevertheless, significant (p < 0.05, paired t test) losses in total nucleated cell numbers were observed if thawed PBPC samples were washed before assay.CONCLUSION: PBPCs can be maintained at 1 to 6°C for up to 3 days and can be cryopreserved after extended storage with properties minimally altered. Dilution alone, without centrifugation and washing, of thawed PBPC samples is a satisfactory procedure for preparing samples for in vitro assays.
Clinical significance of anti‐Jra: report of two cases and review of the literature
Authors: Kwon MeeAe Y. , Su Leon , Arndt Patricia A. , Garratty George , Blackall Douglas P. 
Published: February 2004

BACKGROUND: Jra is a high‐frequency antigen seen in all populations, but the clinical significance of Jra antibodies is incompletely understood. Two cases are reported in which patients with anti‐Jra received incompatible transfusions.CASE REPORTS: A 69‐year‐old Japanese man had anti‐K and anti‐Jra. Despite multiple transfusions of Jr(a+), K– RBCs, his clinical course remained stable without evidence of hemolysis. A 45‐year‐old Japanese woman with anti‐Jra was transfused with two units of Jr(a+) RBCs without clinical evidence of hemolysis. However, the same patient received an additional unit of Jr(a+) RBCs 1 week after the initial transfusions and, within 6 hours of transfusion, developed signs and symptoms of an acute hemolytic transfusion reaction.STUDY DESIGN AND METHODS: Routine serologic methods were used to study the patients’ RBCs and plasma. A monocyte monolayer assay (MMA) was used to determine the potential clinical significance of the anti‐Jra, where reactivity (R) greater than 5 percent indicates potential clinical significance.RESULTS: The anti‐Jra in the first case had a pretransfusion titer of 32 with a MMA result of 3.3 percent R. No clinical or laboratory evidence of hemolysis was seen after transfusion of 4 units of Jr(a+), K– RBCs. The anti‐Jra in the second case had a pretransfusion titer of 32 with a MMA result of 24.5 percent R. This patient developed an acute hemolytic reaction after transfusion of Jr(a+) RBCs.CONCLUSION: Anti‐Jra can be clinically significant as demonstrated by acute hemolysis in the second case. The MMA accurately predicted the clinical outcome of each case and appears to be a useful tool in predicting the biologic behavior of anti‐Jra.
Pediatric large‐volume leukapheresis: a single institution experience with heparin versus citrate‐based anticoagulant regimens
Authors: Bolan Charles D. , Yau Yu Ying , Cullis Herbert C. , Horwitz Mitchell E. , Mackall Crystal L. , John Barrett A. , Malech Harry L. , Rehak Nadja N. , Wayne Alan S. , Leitman Susan F. 
Published: February 2004

BACKGROUND: Anticoagulant‐associated toxicity may exert significant effects on the safety and efficacy of large‐volume leukapheresis (LVL) in children, however, few studies specifically address management of this issue.STUDY DESIGN AND METHODS: Seventy‐four consecutive LVL procedures (mean, 4 blood volumes processed) in children weighing less than or equal to 30 kg (minimum, 10.9 kg) were analyzed. The first 21 procedures were evaluated retrospectively; 11 used heparin alone (Group I) and 10 used heparin plus reduced‐dose ACD‐A (whole blood to anticoagulant ratio ≥20:1) (Group II). The next 53 procedures were evaluated prospectively and used full‐dose ACD‐A (whole blood to anticoagulant ratio ≤13:1), intravenous divalent cation prophylaxis and no heparin; 11 used calcium alone (Group III) followed by 42 with calcium plus magnesium (Group IV).RESULTS: Seventy‐four LVL (56 PBPC and 18 MNC) collections were performed in 38 subjects. One donor in Group I experienced a significant groin hematoma at the site of line placement. One donor each in Groups III and IV had mild paresthesias. Despite a mean citrate infusion rate of 2.6 mg per kg per minute, mean postapheresis serum potassium and ionized magnesium and calcium concentrations in Group IV declined by only 9, 8, and 4 percent, respectively, and stable levels of these variables were maintained 24 hours later. Postapheresis PLT counts declined significantly from baseline preapheresis levels in all groups (mean, 52% decrease).CONCLUSIONS: Use of full‐dose citrate anticoagulant with prophylactic intravenous divalent cation infusion offers an effective and safe approach to management of anticoagulant‐related toxicity in children undergoing LVL.
Wildfire Management in the United States: The Evolution of a Policy Failure
Authors: Busenberg George 
Published: February 2004

AbstractWildland fires constitute a major crisis in American environmental policy, a crisis created by a longstanding policy failure. This article explores the political processes that generated and reinforced this policy failure over time. The concepts of bounded rationality, punctuated equilibria, and self‐ reinforcing mechanisms are applied to study the evolution of American wildfire policy between 1905 and the present. This study finds that a self‐defeating wildfire suppression policy was established in the period 1905 through 1911, and subsequently reinforced for more than five decades. This policy did not include a complementary program to counteract the gradual accumulation of flammable organic materials (fuels) that occurred in many ecosystems when fires were suppressed. The resulting fuel accumulations have greatly increased the risk of damaging, high‐intensity wildfires in a range of American wildlands. A combination of fire suppression and fuel reduction programs will be needed to manage this risk in the future.
“The World Changed Today”: Agenda‐Setting and Policy Change in the Wake of the September 11 Terrorist Attacks
Authors: Birkland Thomas A. 
Published: February 2004

AbstractThe September 11 terrorist attacks constitute a focusing event that have been said to have “changed everything” in America. However, the literature on focusing events, policy change, and the policy process suggests that the “windows of opportunity” opened by focusing events like the September 11 attacks do not automatically equate to policy change. This paper considers whether and to what extent the agenda and policies have changed as a result of the attacks. While the events of September 11 provided the impetus for change, the threat of terrorism was already well established in the policy stream, and September 11 only threw open the window of opportunity for policy change based, in large part, on preexisting ideas; many of these ideas were enacted. And in the case of aviation security, some innovation is evident in the area of cockpit security.
Coastal Oil Pollution: Spills, Crisis, and Policy Change1
Authors: Kurtz Rick S. 
Published: February 2004

AbstractThe federal government's adoption of the Oil Pollution Act of 1990 represented a radical statutory departure from past policy. Coastal oil spill control provisions that had languished for decades within the industry‐friendly confines of a few select congressional subcommittees suddenly became law. Much popular belief credits the 1989 Exxon Valdez spill crisis for bringing about this radical policy change. Closer examination reveals that postcrisis policy change is much more complex. Crisis events intermingle with other short‐ and long‐term factors that either inhibit or support dramatic change. This study analyzes change within the coastal spill arena over several decades. Particular attention is given to crisis episodes, periods identified with a major catastrophe or a successive series of attention‐getting spills over a brief time. Analysis finds that crises can play an instrumental role in eliciting change.
Enron, a Perceived Crisis in Public Confidence, and the Bipartisan Campaign Reform Act of 2002
Authors: Cigler Allan J. 
Published: February 2004

AbstractIn the spring of 2002 Congress passed and President Bush signed the Bipartisan Campaign Reform Act (BCRA), the first major piece of campaign reform legislation since the early 1970s. While momentum for reform had been growing since the mid‐1990s, without the Enron scandal and its potential threat to public officials, additional support to overcome the procedural barriers and opposition from the Republican leadership in both the House and Senate would have been difficult to overcome. In addition, Bush Administration ties to Enron had the effect of demobilizing the president on the issue, making it virtually impossible for him to veto a bill he fundamentally opposed. The Enron scandal provided the “window of opportunity” needed by reform‐oriented elites to pass a controversial and far‐ranging law that was not a high priority on the public's agenda. The end result is a law, pending a Supreme Court ruling on its constitutionality, that has the potential to alter fundamentally how electoral campaigns are funded and conducted.
Assembly Properties of the Human Immunodeficiency Virus Type 1 CA Protein
Authors: Ganser-Pornillos Barbie K. , von Schwedler Uta K. , Stray Kirsten M. , Aiken Christopher , Sundquist Wesley I. 
Published: February 2004

ABSTRACT
During retroviral maturation, the CA protein oligomerizes to form a closed capsid that surrounds the viral genome. We have previously identified a series of deleterious surface mutations within human immunodeficiency virus type 1 (HIV-1) CA that alter infectivity, replication, and assembly in vivo. For this study, 27 recombinant CA proteins harboring 34 different mutations were tested for the ability to assemble into helical cylinders in vitro. These cylinders are composed of CA hexamers and are structural models for the mature viral capsid. Mutations that diminished CA assembly clustered within helices 1 and 2 in the N-terminal domain of CA and within the crystallographically defined dimer interface in the CA C-terminal domain. These mutations demonstrate the importance of these regions for CA cylinder production and, by analogy, mature capsid assembly. One CA mutant (R18A) assembled into cylinders, cones, and spheres. We suggest that these capsid shapes occur because the R18A mutation alters the frequency at which pentamers are incorporated into the hexagonal lattice. The fact that a single CA protein can simultaneously form all three known retroviral capsid morphologies supports the idea that these structures are organized on similar lattices and differ only in the distribution of 12 pentamers that allow them to close. In further support of this model, we demonstrate that the considerable morphological variation seen for conical HIV-1 capsids can be recapitulated in idealized capsid models by altering the distribution of pentamers.
Salmonella osteomyelitis of the thoracic spine: an unusual presentation
Authors: Gupta S K , Pandit A , White D G , Evans P D 
Published: February 2004

Abstract
A case of thoracic vertebral osteomyelitis due to Salmonella enteritidis phage type 2 in an immunocompetent patient is reported. The patient initially presented with abdominal, urinary and chest symptoms, which were followed by a large pleural effusion. The infection was successfully treated with ciprofloxacin. This is the only case of salmonella thoracic vertebral osteomyelitis in an immunocompetent patient reported in the English literature.
Assessing clinical competency in medical senior house officers: how and why should we do it?
Authors: Carr S J 
Published: February 2004

Abstract
Most consultants are involved in the training and assessment of several grades of doctors in training especially senior house officers (SHOs) and specialist registrars. In the medical and other specialties there is an increasing trend towards assessing junior doctors’ competency using the record of in-training assessment process for specialist registrars and using the Royal College of Physicians folder to record competences of medical SHOs. It is necessary to consider why there is a need to assess competency, how it may be done practically, and the advantages and disadvantages of this system of assessment. There are considerable hurdles to the implementation of this system in the medical specialties within today’s NHS and the organisation may need to undergo fairly radical change to facilitate this system.
History of asbestos related disease
Authors: Bartrip P W J 
Published: February 2004

Abstract
The first medical article on the hazards of asbestos dust appeared in the British Medical Journal in 1924. Following inquiries by Edward Merewether and Charles Price, the British government introduced regulations to control dangerous dust emissions in UK asbestos factories. Until the 1960s these appeared to have addressed the problem effectively. Only then, with the discoveries that mesothelioma was an asbestos related disease and that workers other than those employed in the dustiest parts of asbestos factories were at risk, were the nature and scale of the hazard reassessed. In Britain, America, and elsewhere new and increasingly strict regulations were enacted.
PROPERTIES OF ARRANGEMENT GRAPHS
Authors: BOSE PROSENJIT , EVERETT HAZEL , WISMATH STEPHEN 
Published: February 2004

An arrangement graph G is the abstract graph obtained from an arrangement of lines L, in general position by associating vertices of G with the intersection points of L, and the edges of G with the line segments joining the intersection points of L. A simple polygon (respectively path) of n sides in general position, induces a set of n lines by extension of the line segments into lines. The main results of this paper are: • Given a graph G, it is NP-Hard to determine if G is the arrangement graph of some set of lines. • There are non-Hamiltonian arrangement graphs for arrangements of six lines and for odd values of n>6 lines. • All arrangements of n lines contain a subarrangement of size [Formula: see text] with an inducing polygon. • All arrangements on n lines contain an inducing path consisting of n line segments. A Java applet implementing the algorithm for determining such a path is also provided. • All arrangements on n hyperplanes in Rd contain a simple inducing polygonal cycle of size n.
AREA-EFFICIENT ORDER-PRESERVING PLANAR STRAIGHT-LINE DRAWINGS OF ORDERED TREES
Authors: GARG ASHIM , RUSU ADRIAN 
Published: February 2004

Ordered trees are generally drawn using order-preserving planar straight-line grid drawings. We investigate the area-requirements of such drawings and present several results. Let T be an ordered tree with n nodes. We show that: • T admits an order-preserving planar straight-line grid drawing with O(n log n) area. • If T is a binary tree, then T admits an order-preserving planar straight-line grid drawing with O(n log log n) area. • If T is a binary tree, then T admits an order-preserving upward planar straight-line grid drawing with optimalO(n log n) area. We also study the problem of drawing binary trees with user-specified aspect ratios. We show that an ordered binary tree T with n nodes admits an order-preserving planar straight-line grid drawing with area O(n log n), and any user-specified aspect ratio in the range [1,n/ log n]. All the drawings mentioned above can be constructed in O(n) time.
APPROXIMATION OF BELIEF FUNCTIONS
Authors: WEILER THOMAS 
Published: February 2004

This paper addresses the approximation of belief functions by probability functions where the approximation is based on minimizing the Euclidean distance. First of all, we simplify this optimization problem so it becomes equivalent to a standard problem in linear algebra. For the simplified optimization problem, we provide the analytic solution. Furthermore, we show that for Dempster-Shafer belief the simplified optimization problem is equivalent to the original one.In terms of semantics, we compare the approximation of belief functions to various alternative approaches, e.g. pignistic transformation for Dempster-Shafer belief and Shapley value for fuzzy belief functions. For the later one, we give an example where the approximation method has some obvious statistical advantages.Additionally, for the approximation of additive belief functions, we can provide a semantical justification.
PROBING THE LOCAL DENSITY OF STATES OF DILUTE ELECTRON SYSTEMS IN DIFFERENT DIMENSIONS
Authors: MORGENSTERN MARKUS 
Published: February 2004

Scanning tunneling spectroscopy at T = 6 K is used to investigate the local density of states (LDOS) of electron systems belonging to the bulk conduction band of InAs. In particular, the three-dimensional electron system (3DES) of the n-doped material, an adsorbate-induced two-dimensional electron system (2DES) and the tip-induced quantum dot (0DES) are investigated at B = 0 T and B = 6 T. It is found that the 3DES at B = 0 T can be described by Bloch states weakly interacting with the potential disorder provided by ionized dopants. The 2DES at B = 0 T exhibits much stronger LDOS corrugations, stressing the tendency for weak localization in the potential disorder. In a magnetic field, 3DES and 2DES show drift states, which are expected in 2D, but are surprising in 3D, where they point to a new electron phase consisting of droplets of quasi-2D systems. The 0DES at B = 0 T reveals quantized states in accordance with Hartree calculations. At B = 6 T it exhibits Landau states with exchange enhanced spin splitting. These states are used to investigate the influence of potential disorder on the exchange enhancement, which visualizes the nonlocality of the exchange interaction.
Association between obesity and a prothrombotic state: the Framingham Offspring Study
Authors: Rosito Guido , D’Agostino Ralph , Massaro Joseph , Lipinska Izabella , Mittleman Murray , Sutherland Patrice , Wilson Peter , Levy Daniel , Muller James , Tofler Geoffrey 
Published: February 2004

SummaryAlthough obesity is associated with increased cardiovascular risk, the mechanism has not been fully explained. Since thrombosis is a critical component of cardiovascular disease, we examined the relationship between obesity and hemostatic factors. We studied 3230 subjects (55% females, mean age 54 years) without a history of cardiovascular disease in cycle 5 of the Framingham Offspring Study. Obesity was assessed by body mass index and waist-to-hip ratio. Fasting blood samples were obtained for fibrinogen, plasminogen activator inhibitor (PAI-1) antigen, tissue plasminogen activator (tPA) antigen, factor VII antigen, von Willebrand factor (VWF), and plasma viscosity. Body mass index was directly associated with fibrinogen, factor VII, PAI-1 and tPA antigen in both men and women (p<0.001) and with VWF and viscosity in women. Similar associations were present between waist-to-hip ratio and the hemostatic factors. With minor exceptions for VWF and viscosity, all associations persisted after controlling for age, smoking, total and HDL cholesterol, triglycerides, glucose level, blood pressure, and use of antihypertensive medication. The association between increased body mass index and waist-to-hip ratio and prothrombotic factors and impaired fibrinolysis suggests that obesity is a risk factor whose effect is mediated in part by a prothrombotic state.