bluuebunny/crossref_metadata_2025 huggingface dataset:
Carotid Intima-Media Thickness Is Different in Large- and Small-Vessel Ischemic Stroke
Authors: Pruissen D. Martijn O. , Gerritsen Susan A.M. , Prinsen Talitha J. , Dijk Joke M. , Kappelle L. Jaap , Algra Ale
Published: February 2007

Background and Purpose—

The role of athersclerosis in the difference between the pathogenesis of large-vessel disease (LVD) and small-vessel disease (SVD) is a matter of debate. Common carotid artery intima-media thickness (CCA IMT) is a marker of atherosclerosis. Our aim was to compare CCA IMT between SVD and LVD patients.

Methods—

Two independent observers classified ischemic stroke or transient ischemic attack as caused by SVD or LVD, primarily based on imaging and in addition on clinical features. Mean CCA IMT was calculated based on 6 measurements for each patient.

Results—

Four hundred and seventeen patients were classified LVD and 115 SVD. Mean CCA IMT was higher in patients with LVD (1.08 mm) than in patients with SVD (0.92 mm). The crude mean difference was 0.16 mm (95% CI, 0.09 to 0.23). After adjustment for age, sex and hypertension, the mean difference was 0.11 mm (95% CI, 0.05 to 0.18).

Conclusions—

CCA IMT is higher in LVD patients than in SVD patients supporting the hypothesis that LVD and SVD have a different pathogenesis.
The Fab Fragment of a Novel Anti-GPVI Monoclonal Antibody, OM4, Reduces In Vivo Thrombosis Without Bleeding Risk in Rats
Authors: Li Haiquan , Lockyer Simon , Concepcion Alice , Gong Xiaoqi , Takizawa Hisao , Guertin Moe , Matsumoto Yutaka , Kambayashi Junichi , Tandon Narendra N. , Liu Yongge
Published: February 2007

Background—

Inhibition of GPVI has been proposed as a useful antithrombotic strategy; however, in vivo proof-of-concept animal studies targeting GPVI are lacking. We evaluated a novel anti-human GPVI monoclonal antibody OM4 Fab in rats.

Methods and Results—

OM4 Fab specifically inhibited collagen-induced aggregation of rat platelets in vitro with an IC
50
of 20 to 30 μg/mL but not ADP and AA-induced platelet aggregation. After intravenous administration of OM4 Fab, a rapid inhibition of ex vivo platelet aggregation was observed with a gradual recovery within 60 to 90 minutes which corresponded to the decline in OM4 Fab plasma concentration and time-dependent decrease in platelet-bound OM4 Fab. In contrast to previous reports in mice, intravenous OM4 Fab did not deplete platelet GPVI. Injection of OM4 IgG caused acute thrombocytopenia. In a modified Folts model of cyclic flow reduction in rat carotid artery, the number of complete occlusions was significantly reduced by intravenous administration of OM4 Fab (20 mg/kg) before or after mechanical injury to the vessel, without prolongation of bleeding time.

Conclusion—

Fab fragment of the monoclonal antibody OM4 effectively inhibits collagen induced platelet aggregation in vitro and ex vivo, and in vivo thrombosis in rats without prolonging bleeding time. Antibodies against GPVI may have therapeutic potential, inhibiting thrombosis without prolonging bleeding time.
Reed bunting (Emberiza schoeniclus) males sing an 'all-clear' signal to their incubating females
Authors: Wingelmaier Katja , Nemeth Erwin , Winkler Hans
Published: February 2007

While sexual functions of birdsong have been intensively investigated, non-sexual functions have received less attention. After pair formation males may sing to communicate with their established mates. Song aimed at incubating and feeding females could serve as an 'all-clear' signal, showing that there is no risk of predation and that it is safe for the female to exit the nest or to feed the young. Females should therefore preferentially leave nests when mates are singing nearby. Additionally, a vigilant male near the nest site could protect the brood from potential risks like predation and females could stay away longer for foraging. In this study, we investigated aspects of male singing activity of reed buntings (Emberiza schoeniclus) during incubation and feeding of nestlings after pair formation. Exits of incubating females from the nest occurred significantly more often than expected during male song output. When their mates were singing at high rates, females stayed away longer for incubation breaks. During the nestling period we found a high variation in male song output. Males that sang more fed their young significantly less. This suggests that time devoted to singing limits other activities such as feeding of offspring. Male reed buntings could choose different strategies for paternal investment: They either feed at high rates or they sing more to signal their vigilance. Another reason for this trade-off might be a conflict between paternal investment and territory defence or extrapair behaviour. However, even if male song after pairing has additional sexual functions, we suggest that non-sexually selected functions may be more common than expected.
Do turning biases by the 7-spot ladybird, Coccinella septempunctata, increase their foraging efficiency?
Authors: Hassall Mark , Turner John , Girling Robbie
Published: February 2007

The hypothesis that foraging male and female Coccinella septempunctata L. would exhibit a turning bias when walking along a branched linear wire in a Y-maze was tested. Individuals were placed repeatedly in the maze. Approximately 45% of all individuals tested displayed significant turning biases, with a similar number of individuals biased to the left and right. In the maze right-handed individuals turned right at 84.4% of turns and the left-handed individuals turned left at 80.2% of turns. A model of the searching efficiency of C. septempunctata in dichotomous branched environments showed that model coccinellids with greater turning biases discovered a higher proportion of the plant for a given number of searches than those with no bias. A modification of the model to investigate foraging efficiency, by calculating the mean time taken by individuals to find randomly distributed aphid patches, suggested that on four different sizes of plants, with a variety of aphid patch densities, implementing a turning bias was a significantly more efficient foraging strategy than no bias. In general the benefits to foraging of implementing a turning bias increased with the degree of the bias. It may be beneficial for individuals in highly complex branched environments to have a turning bias slightly lower than 100% in order to benefit from increased foraging efficiency without walking in circles. Foraging bias benefits increased with increasing plant size and decreasing aphid density. In comparisons of two different plant morphologies, one with a straight stem and side branches and one with a symmetrically branched morphology, there were few significant differences in the effects of turning biases on foraging efficiency between morphologies.
Population Pharmacokinetic Analysis of the New Oral Thrombin Inhibitor Dabigatran Etexilate (BIBR 1048) in Patients Undergoing Primary Elective Total Hip Replacement Surgery
Authors: Trocóniz Iñaki F. , Tillmann Christiane , Liesenfeld Karl‐Heinz , Schäfer Hans‐Günter , Stangier Joachim
Published: February 2007

Dabigatran etexilate (BIBR 1048) is an orally bioavailable double prodrug of the active principle dabigatran (BIBR 953 ZW), which exerts potent anticoagulant and antithrombotic activity. The objective of the analysis was to develop a population pharmacokinetic model characterizing and quantifying the relationship between covariates and model parameters. A total of 4604 BIBR 953 ZW plasma concentrations, obtained from 287 patients after once‐ or twice‐daily oral dosing for up to 10 days after surgery in the dose range 12.5, 25, 50, 100, 150, 200, and 300 mg BIBR 1048, were available for the analysis. All the analyses were performed with NONMEN V. Pharmacokinetics of dabigatran were best described by a 2‐compartment model. The data supported the estimation of different apparent first‐order absorption rate constants (ka) and apparent plasma clearances (CL/F) for days 0 and 1 and days 2 to 10 after surgery. Parameter estimates indicated a flip‐flop phenomenon. Age and serum creatinine influenced ka, whereas gastrin and creatinine clearance, only for days 2 to 10, affected CL/F (P < .001). The typical values for CL/F for a patient with gastrin of 34.58 pmol/L and creatinine clearance of 76.16 mL/min were 70.87 and 106.2 L/h on days 0 and 1 and days 2 to 10, respectively. The differences found in the pharmacokinetics of dabigatran during the first 24 hours after surgery are most likely due to alterations in gastric motility and pH following surgery. As a consequence, the rate of absorption is reduced and interindividual variability in drug exposure increased. On the following days, the disposition in plasma of BIBR 953 ZW is less variable.
Pharmacokinetics and Safety of Golimumab, a Fully Human Anti‐TNF‐α Monoclonal Antibody, in Subjects With Rheumatoid Arthritis
Authors: Zhou Honghui , Jang Haishan , Fleischmann Roy M. , Bouman‐Thio Esther , Xu Zhenhua , Marini Joseph C. , Pendley Charles , Jiao Qun , Shankar Gopi , Marciniak Stanley J. , Cohen Stanley B. , Rahman Mahboob U. , Baker Daniel , Mascelli Mary Ann , Davis Hugh M. , Everitt Daniel E.
Published: February 2007

Golimumab is a fully human antitumor necrosis factor alpha (TNF‐α) monoclonal antibody that is being developed for intravenous and subcutaneous administration. To assess the pharmacokinetics and safety of the intravenous formulation of golimumab, 36 adult subjects with rheumatoid arthritis were randomly assigned to receive a single infusion of placebo or golimumab (0.1, 0.3, 1, 3, 6, or 10 mg/kg). Serum concentrations of golimumab were determined using a validated enzyme‐linked immunosorbent assay method. In addition to the noncompartmental analysis and compartmental modeling, a population pharmacokinetics analysis using NONMEM was also conducted. Both the maximum serum concentration and the area under the serum concentration‐time curve appeared to increase in a dose‐proportional manner. The median half‐life ranged from 7 to 20 days. A 2‐compartment population pharmacokinetic model adequately described the pharmacokinetics of golimumab. The following pharmacokinetic parameters (typical value [% coefficient of variation]) were estimated from the population pharmacokinetic model: clearance (CL: 0.40 [10.1%] L/d), volume of distribution in the central compartment (Vc: 3.07 [6.4%] L), intercompartmental clearance (Q: 0.42 [15.5%] L/d), and volume of distribution in the peripheral compartment (Vp: 3.68 [11.8%] L). Interindividual variability of the pharmacokinetic parameters was quantified for CL (44.3%), Vc (25.5%), Q (44.6%), and Vp (44.6%). Residual variability was estimated to be 15.0%. Body weight was found to be an important covariate on Vc. Golimumab was generally well tolerated. The pharmacokinetics of golimumab appeared to be linear over the dose range evaluated in this study.
Dasatinib or high-dose imatinib for chronic-phase chronic myeloid leukemia after failure of first-line imatinib: a randomized phase 2 trial
Authors: Kantarjian Hagop , Pasquini Ricardo , Hamerschlak Nelson , Rousselot Philippe , Holowiecki Jerzy , Jootar Saengsuree , Robak Tadeusz , Khoroshko Nina , Masszi Tamas , Skotnicki Aleksander , Hellmann Andrzej , Zaritsky Andrey , Golenkov Anatoly , Radich Jerald , Hughes Timothy , Countouriotis Athena , Shah Neil
Published: February 2007

Therapeutic options for chronic myelogenous leukemia (CML) resistant to 400 to 600 mg imatinib are limited. Escalating imatinib doses may overcome resistance. Dasatinib, a significantly more potent inhibitor of BCR-ABL, is safe and effective in this population. Patients with imatinib-resistant chronic-phase (CP) CML were randomized 2:1 to 140 mg dasatinib (n = 101) or 800 mg imatinib (n = 49). With a median follow up of 15 months, complete hematologic responses were observed in 93% and 82% of patients receiving dasatinib and high-dose imatinib (P = .034), respectively. Dasatinib resulted in higher major cytogenetic response rates (52%) than high-dose imatinib (33%) (P = .023); this included complete cytogenetic response in 40% and 16% (P = .004). Major molecular responses were also more frequent with dasatinib (16% versus 4%; P = 0.038). Treatment failure (hazard ratio [HR], 0.16; P < .001) and progression-free survival (HR, 0.14; P < .001) both favored dasatinib. Superficial edema (42% versus 15%) and fluid retention (45% versus 30%) were more prevalent with imatinib; pleural effusion was more common with dasatinib (17% versus 0%). Grade 3 to 4 nonhematologic toxicity was minimal. Cytopenias were more frequent and severe with dasatinib. Dasatinib represents a safe and effective therapy for CP-CML resistant to conventional imatinib doses with improved cytogenetic and molecular response rates and progression-free survival relative to high-dose imatinib.
β-Catenin stabilization stalls the transition from double-positive to single-positive stage and predisposes thymocytes to malignant transformation
Authors: Guo Zhuyan , Dose Marei , Kovalovsky Damian , Chang Rui , O'Neil Jennifer , Look A. Thomas , von Boehmer Harald , Khazaie Khashayarsha , Gounari Fotini
Published: February 2007

Activation of β-catenin has been causatively linked to the etiology of colon cancer. Conditional stabilization of this molecule in pro-T cells promotes thymocyte development without the requirement for pre-TCR signaling. We show here that activated β-catenin stalls the developmental transition from the double-positive (DP) to the single-positive (SP) thymocyte stage and predisposes DP thymocytes to transformation. β-Catenin–induced thymic lymphomas have a leukemic arrest at the early DP stage. Lymphomagenesis requires Rag activity, which peaks at this developmental stage, as well as additional secondary genetic events. A consistent secondary event is the transcriptional up-regulation of c-Myc, whose activity is required for transformation because its conditional ablation abrogates lymphomagenesis. In contrast, the expression of Notch receptors as well as targets is reduced in DP thymocytes with stabilized β-catenin and remains low in the lymphomas, indicating that Notch activation is not required or selected for in β-catenin–induced lymphomas. Thus, β-catenin activation may provide a mechanism for the induction of T-cell–acute lymphoblastic leukemia (T-ALL) that does not depend on Notch activation.
Comparing health system performance assessment and management approaches in the Netherlands and Ontario, Canada
Authors: Tawfik-Shukor Ali R , Klazinga Niek S , Arah Onyebuchi A
Published: February 2007

Background

Given the proliferation and the growing complexity of performance measurement initiatives in many health systems, the Netherlands and Ontario, Canada expressed interests in cross-national comparisons in an effort to promote knowledge transfer and best practise. To support this cross-national learning, a study was undertaken to compare health system performance approaches in The Netherlands with Ontario, Canada.

Methods

We explored the performance assessment framework and system of each constituency, the embeddedness of performance data in management and policy processes, and the interrelationships between the frameworks. Methods used included analysing governmental strategic planning and policy documents, literature and internet searches, comparative descriptive tables, and schematics. Data collection and analysis took place in Ontario and The Netherlands. A workshop to validate and discuss the findings was conducted in Toronto, adding important insights to the study.

Results

Both Ontario and The Netherlands conceive health system performance within supportive frameworks. However they differ in their assessment approaches. Ontario's Scorecard links performance measurement with strategy, aimed at health system integration. The Dutch Health Care Performance Report (Zorgbalans) does not explicitly link performance with strategy, and focuses on the technical quality of healthcare by measuring dimensions of quality, access, and cost against healthcare needs. A backbone 'five diamond' framework maps both frameworks and articulates the interrelations and overlap between their goals, themes, dimensions and indicators. The workshop yielded more contextual insights and further validated the comparative values of each constituency's performance assessment system.

Conclusion

To compare the health system performance approaches between The Netherlands and Ontario, Canada, several important conceptual and contextual issues must be addressed, before even attempting any future content comparisons and benchmarking. Such issues would lend relevant interpretational credibility to international comparative assessments of the two health systems.
Post-traumatic stress disorder and post-traumatic stress symptoms following critical illness in medical intensive care unit patients: assessing the magnitude of the problem
Authors: Jackson James C , Hart Robert P , Gordon Sharon M , Hopkins Ramona O , Girard Timothy D , Ely EWesley
Published: February 2007

Introduction

Post-traumatic stress disorder (PTSD) is a potentially serious psychiatric disorder that has traditionally been associated with traumatic stressors such as participation in combat, violent assault, and survival of natural disasters. Recently, investigators have reported that the experience of critical illness can also lead to PTSD, although details of the association between critical illness and PTSD remain unclear.

Methods

We conducted keyword searches of MEDLINE and Psych Info and investigations of secondary references for all articles pertaining to PTSD in medical intensive care unit (ICU) survivors.

Results

From 78 screened papers, 16 studies (representing 15 cohorts) and approximately 920 medical ICU patients met inclusion criteria. A total of 10 investigations used brief PTSD screening tools exclusively as opposed to more comprehensive diagnostic methods. Reported PTSD prevalence rates varied from 5% to 63%, with the three highest prevalence estimates occurring in studies with fewer than 30 patients. Loss to follow-up rates ranged from 10% to 70%, with average loss to follow-up rates exceeding 30%.

Conclusion

Exact PTSD prevalence rates cannot be determined due to methodological limitations such as selection bias, loss to follow-up, and the wide use of screening (as opposed to diagnostic) instruments. In general, the high prevalence rates reported in the literature are likely to be overestimates due to the limitations of the investigations conducted to date. Although PTSD may be a serious problem in some survivors of critical illness, data on the whole population are inconclusive. Because the magnitude of the problem posed by PTSD in survivors of critical illness is unknown, there remains a pressing need for larger and more methodologically rigorous investigations of PTSD in ICU survivors.
Meperidine and skin surface warming additively reduce the shivering threshold: a volunteer study
Authors: Kimberger Oliver , Ali Syed Z , Markstaller Monica , Zmoos Sandra , Lauber Rolf , Hunkeler Corinne , Kurz Andrea
Published: February 2007

Introduction

Mild therapeutic hypothermia has been shown to improve outcome for patients after cardiac arrest and may be beneficial for ischaemic stroke and myocardial ischaemia patients. However, in the awake patient, even a small decrease of core temperature provokes vigorous autonomic reactions–vasoconstriction and shivering–which both inhibit efficient core cooling. Meperidine and skin warming each linearly lower vasoconstriction and shivering thresholds. We tested whether a combination of skin warming and a medium dose of meperidine additively would reduce the shivering threshold to below 34°C without producing significant sedation or respiratory depression.

Methods

Eight healthy volunteers participated on four study days: (1) control, (2) skin warming (with forced air and warming mattress), (3) meperidine (target plasma level: 0.9 μg/ml), and (4) skin warming plus meperidine (target plasma level: 0.9 μg/ml). Volunteers were cooled with 4°C cold Ringer lactate infused over a central venous catheter (rate ≈ 2.4°C/hour core temperature drop). Shivering threshold was identified by an increase of oxygen consumption (+20% of baseline). Sedation was assessed with the Observer's Assessment of Alertness/Sedation scale.

Results

Control shivering threshold was 35.5°C ± 0.2°C. Skin warming reduced the shivering threshold to 34.9°C ± 0.5°C (p = 0.01). Meperidine reduced the shivering threshold to 34.2°C ± 0.3°C (p < 0.01). The combination of meperidine and skin warming reduced the shivering threshold to 33.8°C ± 0.2°C (p < 0.01). There were no synergistic or antagonistic effects of meperidine and skin warming (p = 0.59). Only very mild sedation occurred on meperidine days.

Conclusion

A combination of meperidine and skin surface warming reduced the shivering threshold to 33.8°C ± 0.2°C via an additive interaction and produced only very mild sedation and no respiratory toxicity.
Long-term prevalence of post-traumatic stress disorder symptoms in patients after secondary peritonitis
Authors: Boer Kimberly R , Mahler Cecilia W , Unlu Cagdas , Lamme Bas , Vroom Margreeth B , Sprangers Mirjam A , Gouma Dirk J , Reitsma Johannes B , De Borgie Corianne A , Boermeester Marja A
Published: February 2007

Introduction

The aim of this study was to determine the long-term prevalence of post-traumatic stress disorder (PTSD) symptomology in patients following secondary peritonitis and to determine whether the prevalence of PTSD-related symptoms differed between patients admitted to the intensive care unit (ICU) and patients admitted only to the surgical ward.

Method

A retrospective cohort of consecutive patients treated for secondary peritonitis was sent a postal survey containing a self-report questionnaire, namely the Post-traumatic Stress Syndrome 10-question inventory (PTSS-10). From a database of 278 patients undergoing surgery for secondary peritonitis between 1994 and 2000, 131 patients were long-term survivors (follow-up period at least four years) and were eligible for inclusion in our study, conducted at a tertiary referral hospital in Amsterdam, The Netherlands.

Results

The response rate was 86%, yielding a cohort of 100 patients; 61% of these patients had been admitted to the ICU. PTSD-related symptoms were found in 24% (95% confidence interval 17% to 33%) of patients when a PTSS-10 score of 35 was chosen as the cutoff, whereas the prevalence of PTSD symptomology when borderline patients scoring 27 points or more were included was 38% (95% confidence interval 29% to 48%). In a multivariate analyses controlling for age, sex, Acute Physiology and Chronic Health Evaluation II (APACHE II) score, number of relaparotomies and length of hospital stay, the likelihood of ICU-admitted patients having PTSD symptomology was 4.3 times higher (95% confidence interval 1.11 to 16.5) than patients not admitted to the ICU, using a PTSS-10 score cutoff of 35 or greater. Older patients and males were less likely to report PTSD symptoms.

Conclusion

Nearly a quarter of patients receiving surgical treatment for secondary peritonitis developed PTSD symptoms. Patients admitted to the ICU were at significantly greater risk for having PTSD symptoms after adjusting for baseline differences, in particular age.
Boosting with stumps for predicting transcription start sites
Authors: Zhao Xiaoyue , Xuan Zhenyu , Zhang Michael Q
Published: February 2007

Promoter prediction is a difficult but important problem in gene finding, and it is critical for elucidating the regulation of gene expression. We introduce a new promoter prediction program, CoreBoost, which applies a boosting technique with stumps to select important small-scale as well as large-scale features. CoreBoost improves greatly on locating transcription start sites. We also demonstrate that by further utilizing some tissue-specific information, better accuracy can be achieved.
Leptin and the Control of Food Intake: Neurons in the Nucleus of the Solitary Tract Are Activated by Both Gastric Distension and Leptin
Authors: Huo Lihong , Maeng Lisa , Bjørbæk Christian , Grill Harvey J.
Published: February 2007

Leptin reduces food intake by an unspecified mechanism. Studies show that forebrain ventricular leptin delivery increases the inhibitory effects of gastrointestinal (GI) stimulation on intake and amplifies the electrophysiological response to gastric distension in neurons of the medial subnucleus of the nucleus tractus solitarius (mNTS). However, forebrain ventricular delivery leaves unspecified the neuroanatomical site(s) mediating leptin’s effect on intake. Detailed anatomical analysis in rats and mice by phosphorylated signal transducer and activator of transcription 3 immunohistochemistry shows that hindbrain leptin-responsive neurons are located exclusively within the mNTS. Here, we investigate 1) whether leptin and gastric distension affect the same mNTS neurons and 2) whether the intake-inhibitory action of gastric distension is potentiated by hindbrain leptin delivery. Twenty-five minutes after gastric balloon distension or sham distension, rats were injected with leptin or vehicle and killed 35 min later. Double-fluorescent immunohistochemistry for phosphorylated signal transducer and activator of transcription 3 and c-Fos revealed that about 40% of leptin-responsive cells also respond to gastric distension. A paradigm was then developed to examine the relationship between leptin and gastric distension volume on intake inhibition. At subthreshold levels, hindbrain ventricular leptin or distension volume were without effect. When combined, an interaction occurred that significantly reduced food intake. We conclude that 1) leptin-responsive neurons in the hindbrain are primarily located in the mNTS at the level of the area postrema, a key vagal afferent projection zone of the GI system; 2) a significant proportion of leptin-responsive neurons in the mNTS are activated by stomach distension; and 3) leptin delivered to the hindbrain is sufficient to potentiate the intake-suppressive effects of an otherwise ineffective volume of gastric distension. These results are consistent with the hypothesis that leptin acts directly on neurons within the mNTS to reduce food intake through an interaction with GI signal processing.
The Economic Lives of the Poor
Authors: Banerjee Abhijit V , Duflo Esther
Published: February 2007

The 1990 World Development Report from the World Bank defined the “extremely poor” people of the world as those who are currently living on no more than $1 per day per person. But how actually does one live on less than $1 per day? This essay is about the economic lives of the extremely poor: the choices they face, the constraints they grapple with, and the challenges they meet. A number of recent data sets and a body of new research allow us to start building an image of the way the extremely poor live their lives. Our discussion builds on household surveys conducted in 13 countries: Cote d'Ivoire, Guatemala, India, Indonesia, Mexico, Nicaragua, Pakistan, Panama, Papua New Guinea, Peru, South Africa, Tanzania, and Timor Leste (East Timor). These surveys provide detailed information on extremely poor households around the world, from Asia to Africa to Latin America, including information on what they consume, where they work, and how they save and borrow. We consider the extremely poor—those living in households where the consumption per capita is less than $1.08 per person per day—as well as the merely “poor”—defined as those who live under $2.16 a day—using 1993 purchasing power parity as benchmark. In keeping with convention, we call these the $1 and $2 dollar poverty lines, respectively.
How Progressive is the U.S. Federal Tax System? A Historical and International Perspective
Authors: Piketty Thomas , Saez Emmanuel
Published: February 2007

This paper provides estimates of federal tax rates by income groups in the United States since 1960, with special emphasis on very top income groups. We include individual and corporate income taxes, payroll taxes, and estate and gift taxes. The progressivity of the U.S. federal tax system at the top of the income distribution has declined dramatically since the 1960s. This dramatic drop in progressivity is due primarily to a drop in corporate taxes and in estate and gift taxes combined with a sharp change in the composition of top incomes away from capital income and toward labor income. The sharp drop in statutory top marginal individual income tax rates has contributed only moderately to the decline in tax progressivity. International comparisons confirm that is it critical to take into account other taxes than the individual income tax to properly assess the extent of overall tax progressivity, both for time trends and for cross-country comparisons. The pattern for the United Kingdom is similar to the U.S. pattern. France had less progressive taxes than the United States or the United Kingdom in 1970 but has experienced an increase in tax progressivity and has now a more progressive tax system than the United States or the United Kingdom.
Performance of rapid HIV testing using Determine® HIV-1/2 for the diagnosis of HIV infection during pregnancy in Tijuana, Baja California, Mexico
Authors: Viani R M , Hubbard P , Ruiz-Calderon J , Araneta M R G , Lopez G , Chacón-Cruz E , Spector S A
Published: February 2007

The aim of this study was to evaluate the performance of the rapid antibody test Determine® HIV-1/2, in pregnant women at Tijuana General Hospital. Pregnant women seeking prenatal care or admitted in labour had blood drawn for a rapid HIV test (Determine® HIV-1/2), enzyme immunoassay (EIA) and Western blot. Between March and November 2003, 1068 women in labour and 1529 women in prenatal care were enrolled. The sensitivity, specificity, positive and negative predictive values were 100%, 99.8%, 77% and 100%, respectively. For women in labour, the mean time between blood collection and rapid test results was 92 minutes (range: 20–205 minutes) compared with 41 hours (range 24–120 hours) for HIV EIA ( P = 0.012). All HIV-exposed infants received oral zidovudine. These findings indicate that the rapid test Determine® HIV-1/2 has a high sensitivity and specificity in pregnant women. Rapid HIV testing greatly diminishes the time to diagnosis and enables prompt intervention with antiretrovirals at delivery.
The Mental Capacity Act 2005
Authors: Sheather Julian
Published: February 2007

The Mental Capacity Act, which received Royal Assent in April 2005, will come into force in April 2007. The Act puts into statute the legality of interventions in relation to adults who lack capacity to make decisions on their own behalf. The aim of this paper is to outline the main features of the legislation and its impact on those health care professionals who provide care and treatment for incapacitated adults. The paper sets out the underlying ethical principles that govern interventions under the Act's powers and briefly explores the legal definition of incapacity and the process by which capacity is assessed. It looks at the governing notion of 'best interests' and at the legal indemnity provided by the Act for interventions that are in the best interests of an incapacitated adult. It contains sections on the Act's main innovations, including research involving incapacitated adults, lasting powers of attorney and the new Court of Protection. It also provides information on advance decisions to refuse treatment.
Coordinated Replenishment Strategies in Inventory/Distribution Systems
Authors: Gürbüz Mustafa Çagri , Moinzadeh Kamran , Zhou Yong-Pin
Published: February 2007

In this paper, we study the impact of coordinated replenishment and shipment in inventory/distribution systems. We analyze a system with multiple retailers and one outside supplier. Random demand occurs at each retailer, and the supplier replenishes all the retailers. In traditional inventory models, each retailer orders directly from the supplier whenever the need arises. We present a new, centralized ordering policy that orders for all retailers simultaneously. The new policy is equivalent to the introduction of a warehouse with no inventory that is in charge of the ordering, allocation, and distribution of inventory to the retailers. Under such a policy, orders for some retailers may be postponed or expedited so that they can be batched with other retailers’ orders, which results in savings in ordering and shipping costs. In addition to the policy we propose for supplying inventory to the retailers, we also consider three other policies that are based on these well-known policies in the literature: (a) can-order policy, (b) echelon inventory policy, and (c) fixed-replenishment interval policy. Furthermore, we create a framework for simultaneously making inventory and transportation decisions by incorporating the transportation costs (or limited truck capacities). We numerically compare the performance of our proposed policy with these policies to identify the settings in which each policy would perform well.
An Extreme Value Approach to Estimating Interest-Rate Volatility: Pricing Implications for Interest-Rate Options
Authors: Bali Turan G.
Published: February 2007

This paper proposes an extreme value approach to estimating interest-rate volatility, and shows that during the extreme movements of the U.S. Treasury market the volatility of interest-rate changes is underestimated by the standard approach that uses the thin-tailed normal distribution. The empirical results indicate that (1) the volatility of maximal and minimal changes in interest rates declines as time-to-maturity rises, yielding a downward-sloping volatility curve for the extremes; (2) the minimal changes are more volatile than the maximal changes for all data sets and for all asymptotic distributions used; (3) the minimal changes in Treasury yields have fatter tails than the maximal changes; and (4) for both the maxima and minima, the extreme changes in short-term rates have thicker tails than the extreme changes in long-term rates. This paper extends the standard option-pricing models with lognormal forward rates to accommodate significant kurtosis observed in the interest-rate data. This paper introduces a closed-form option-pricing model based on the generalized extreme value distribution that successfully removes the well-known pricing bias of the lognormal distribution.
Sonication-Laser-Excited Time-Resolved Shpol'skii Spectrometry: A Facile Method for the Direct Screening of Fifteen Priority Pollutants in Soil Samples
Authors: Yu Shenjiang , Goicoechea Hector C. , Campiglia Andres D.
Published: February 2007

A unique method for screening polycyclic aromatic hydrocarbons (PAH) in soil samples is reported. Milligrams of soil are sonicated into the vial of a cryogenic fiber-optic probe with 250 μL of n-octane. Pollutants partition into the layer of extracting solvent and the cryogenic probe is then used for fluorescence measurements at liquid helium temperature (4.2 K). N-octane provides PAH with the appropriate Shpol'skii matrix to record highly resolved spectra and characteristic fluorescence lifetimes. Unambiguous PAH determination is directly performed from the layer of extracting solvent with no need for previous PAH separation. The total analysis time from the extraction to PAH identification is approximately 35 min per sample. Limits of detection are at the sub-parts per billion levels. PAH recoveries are similar to those obtained via high-performance liquid chromatography analysis. The simplicity of the experimental procedure, the short analysis time, the selectivity, and the excellent analytical figures of merit demonstrate the advantages of this approach for routine analysis of soil samples.
Relative Intensity Correction of Raman Spectrometers: NIST SRMs 2241 through 2243 for 785 nm, 532 nm, and 488 nm/514.5 nm Excitation
Authors: Choquette Steven J. , Etz Edgar S. , Hurst Wilbur S. , Blackburn Douglas H. , Leigh Stefan D.
Published: February 2007

Standard Reference Materials® SRMs 2241 through 2243 are certified spectroscopic standards intended for the correction of the relative intensity of Raman spectra obtained with instruments employing laser excitation wavelengths of 785 nm, 532 nm, or 488 nm/514.5 nm. These SRMs each consist of an optical glass that emits a broadband luminescence spectrum when illuminated with the Raman excitation laser. The shape of the luminescence spectrum is described by a polynomial expression that relates the relative spectral intensity to the Raman shift with units in wavenumber (cm−1). This polynomial, together with a measurement of the luminescence spectrum of the standard, can be used to determine the spectral intensity-response correction, which is unique to each Raman system. The resulting instrument intensity-response correction may then be used to obtain Raman spectra that are corrected for a number of, but not all, instrument-dependent artifacts. Peak area ratios of the intensity-corrected Raman spectrum of cyclohexane are presented as an example of a methodology to validate the spectral intensity calibration process and to illustrate variations that can occur in this measurement.
Far Infrared and Raman Spectra of (CH3)3SiCo(CO)4
Authors: Durig J. R. , Meischen S. J. , Hannum S. E. , Hitch R. R. , Gondal S. K. , Sears C. T.
Published: February 2007

The ir spectra of (CH3)3SiCo(CO)4 in the gaseous (4000–250 cm−1) and solid (4000–33 cm−1) phases have been recorded. The Raman spectrum has also been recorded for the solid state. To aid in the assignment, the ir and Raman spectra were recorded of solid (CH3)3SiH. The vibrational assignment for most of the 60 normal modes has been given on the basis of the fundamental vibrations of the –Si(CH3)3 and –Co(CO)4 moities. The static field was sufficiently strong to split the degenerate modes but the correlation field was so weak that no definite splitting of the symmetric modes was detected.
Spectrographic Determination of Elements in Airborne Dirt
Authors: Lander D. W. , Steiner R. L. , Anderson D. H. , Dehm R. L.
Published: February 2007

An emission spectrographic method is described to determine the concentrations of aluminum, cadmium, calcium, chromium, copper, iron, lead, magnesium, nickel, silicon, tin, and zinc in airborne dirt. A measured volume of air is drawn through a 1 in. filter paper. The filter is analyzed by a direct reading emission spectrograph using a push-up technique to introduce the sample into the analytical gap. Calculations and report writing are performed by a computer. Computer programs aid the data interpretation by annotating the results and by the preparation of summaries and graphs. The precision is approximately ±25% of the amount present at the 3 µg level. Analysis time is about 5 min/sample.
Use of Soft X-Ray Band Spectra for Determining Molecular Orbital Structure. I. Vanadium Octahedral and Tetrahedral Sites
Authors: Fischer David W.
Published: February 2007

A molecular orbital model is used as the basis for interpreting the metal ion K and Lii,iii, x-ray spectra and the oxygen K spectra for both octahedral and tetrahedral vanadium–oxygen compounds Specific electronic transitions are assigned to each intensity maximum in both emission and absorption spectra. It is shown that by combining the information contained in all the spectra a complete molecular-orbital (MO) energy level diagram can be empirically deduced for each compound. Individual MO's can be accurately placed with respect to each other making the x-ray technique a most powerful experimental tool for probing the electronic structure of simple compounds.
A Quantitative Evaluation of Several Infrared Searching Systems
Authors: Erley D. S.
Published: February 2007

Infrared file searching programs must try to achieve high relevance while allowing for errors between the coded standard data and the unknown. A scoring system has been devised so that individual searches can be quantitatively evaluated; this also allows the overall performance of the search algorithm to be calculated. Several searching programs for the ASTM ir data file are compared using a test group of 138 unknown spectra selected at random from the literature. Search costs and a cost/performance ratio are also calculated for each system.
Molecular Orientation and Absorbance Determination for Oriented Polymers by Tilting Method with Nonpolarized Infrared Light
Authors: Koenig J. L. , Itoga M.
Published: February 2007

A new method of measuring the absorbance corrected for orientation and the orientation of oriented polymer systems is derived. The method using unpolarized light utilizes a linear plotting and extrapolation technique to minimize experimental errors. The method is applied to oriented nlyon 66 samples and the results are compared with the previous methods.
X-Ray Fluorescence Determination of Barium and Strontium in Geologic Samples
Authors: Fabbi Brent P.
Published: February 2007

It is possible to accurately determine barium and strontium in a variety of geologic samples by the XRF method proposed herein after correcting for matrix effects. The first-order (I) titanium Kα1 line interferes spectrally with the barium first-order (I) Lα1 analytical line. Iron significantly absorbs the emitted strontium x-ray quanta. Both of these effects were investigated in detail and a method of correcting for them developed. Detection limit for both elements is about 10 ppm.
Free Atom Production in a Stabilized dc Arc Device for Atomic Absorption Spectrometry
Authors: Marinković M. , Vickers T. J.
Published: February 2007

A long-path stabilized dc arc device is described, and the results of an investigation of free atom production with this device reported. In all the measurements reported samples were introduced to the arc as solution aerosols. In evaluation of the arc the following aspects were examined: (1) the effect of current, (2) the effect of potassium addition, (3) the effect of hydrocarbon addition. Radial absorbance measurements are reported for Mg, Al, and W. Atomic absorption detection limits are reported for Al, B, Mg, V, and W.
Metal Isotope Effect on Raman Spectrum of [Zn(NH3)4]I2 Crystals
Authors: Nakamoto Kazuo , Takemoto James , Chow T. L.
Published: February 2007

The Raman spectra of [64Zn(NH3)4]I2 and its 68Zn analog have been measured in the crystalline state. The Zn–N stretching vibrations have been assigned based on the observed metal isotope shifts. These shifts have been compared with theoretical values obtained from a complete normal coordinate analysis on the [Zn(NH3)4]2+ ion.
Physical and Analytical Aspects of a Microwave Excited Plasma
Authors: Fallgatter Karen , Svoboda V. , Winefordner J. D.
Published: February 2007

A microwave generator operated at about 100 W was used to maintain a narrow plasma (6 cm long ×0.3 mm diam) in flowing argon at atmospheric pressure. A tapered rectangular cavity was used to couple microwave power to the plasma discharge. Approximate temperature and electron density measurements of the plasma were made with and without water being nebulized; the temperature measurements indicated a lack of thermodynamic equilibrium. The plasma discharge was examined as a source of excitation in atomic emission spectrometry. An aerosol (produced by a system consisting of a pneumatic sprayer, a heated chamber, and a special condenser) was introduced into a plasma having an excitation and ionization temperature of about 5000 K and an electron density of about 1015 cm−3 at a position 0.3 mm from the center of the plasma. Limits of detection were measured for cadmium, gallium, indium, mercury, and zinc. Appreciable signals were also observed for calcium, lead, strontium, and boron, but no limits of detection were measured.
Piezoelectrically Induced Selective Flame Signal Modulation
Authors: Mossotti Victor G. , Abercrombie Frank N. , Eakin Judith A.
Published: February 2007

The design and performance of two devices for selective spectral modulation in flame emission and atomic absorption spectrometry are reported. The similar techniques use periodic piezoelectrically induced deformation of one or two fluidic channels to the solution nebulizer. The mechanically simpler channel device generates a regular ac ripple on the solution flow into the flame. In certain situations, the influence of the solvent pulsing on the flame temperature permits the differentiation of flame background signals from signals of analytical interest; alternatively, advantage can be taken of mutually compensating flame processes which negate the influence of solvent modulation on the flame background. In the generally applicable dual channel technique, the nominal solution uptake rate is constant and the ac components in the flame spectra represent the differences in chemical composition between the analytical and the blank solutions. Effective background discrimination ratios for certain band systems exceed 103:1.
Applications of Nuclear Quadrupole Resonance Spectrometry to Analytical Chemistry
Authors: Schultz Harry D.
Published: February 2007

Since Dehmelt [H. Dehmelt and H. Krüger, Naturwiss. 37, 11 (1950)] observed the first pure quadrupole resonance signal in 1949, this technique has been developed to a high degree of sophistication for the investigation of bonding and structural features in compounds. Most of the early-data were obtained on organic halides. More recently, NQR has been used to research inorganic bonding characteristics such as π and σ bonding in nitrogen compounds and transition metal complexes. The technique has also been extensively developed for mineralogical research, including recent applications for quantitative analysis of specific minerals in natural ore deposits. The major developments in instrumentation which were made in an effort to solve these problems are discussed.
Safety Interlock for Raman Spectrometer Laser Beam
Authors: Bartz A. M. , Pratt C. B. , Kagel R. O.
Published: February 2007

A Raman spectrometer equipped with a 350 mW laser required a means to confine and reduce the laser beam intensity to avoid eye injury. This is a description of the filter–shutter system designed to reduce the likelihood of an accidental exposure.
ΔMs = ±2 Transitions of Benzophenone and Derivatives in the Phosphorescent Triplet State via Fast-Scan Flash-Synchronized ESR
Authors: Yamanashi Bill S. , Mazza Carl , Bowers Kerry W.
Published: February 2007

Δ M8 = ±2 transitions of benzophenone, p-hydroxybenzophenone, p-methyl-benzophenone, p-aminobenzophenone, benzyl, xanthane-9-one, fluorene-9-one, and thio-xanthane-9-one in EPA glass at 77 K were observed with a fast-scan flash-synchronized X-band ESR spectrometer. Instrumentation which may be useful in the observation of Δ M8 = ±2 transitions in similar short-lived S≠O molecules is discussed.
Recording Raman Spectra of Polymers
Authors: Gall M. J. , Hendra P. J. , Watson D. S. , Peacock C. J.
Published: February 2007

A description of a number of methods of recording laser–Raman spectra of polymers is given. In particular, methods of obtaining adequate depolarization ratios in turbid species and avoidance of fluorescence are stressed. Consideration is also given to anisotropic scattering in oriented specimens and the interpretation of the effects observed.
The Practical Analysis of High-Purity Chemicals. VI. Emission Spectrographic Analysis of High-Purity Acids
Authors: Kershner N. A. , Joy E. F. , Barnard A. J.
Published: February 2007

The spectrographic analysis of volatile acids in a high-purity form is reviewed and a procedure presented that involves evaporation of a 100-g sample under temperature controlled contamination-free conditions and emission spectrography using dc-arc excitation under controlled atmosphere. In the evaporation, graphite (10 mg) is added as a collector, sulfuric acid to convert to less volatile sulfates (with acetic, hydrochloric, and nitric acids), and also mannitol to retain boron (with hydrochloric and hydrofluoric acids). Indium is added as a internal standard. Spectra are examined for 33 elements against a multielement standard in graphite containing indium as an internal standard. For the concurrent analysis of three samples, the elapsed time is 4–10 h and the actual working time 3–5 h. Recovery studies are reported as well as the use of the procedure in the assessment of the leaching of borosilicate glass by concentrated mineral acids.