bluuebunny/crossref_metadata_2025 huggingface dataset:
Implementation of Community‐based Public Access Defibrillation in the PAD Trial
Authors: Richardson Lynne D. , Gunnels Mary D. , Groh William J. , Peberdy Mary Ann , Pennington Sarah , Wilets Ilene , Campbell Venard , Van Ottingham Lois , McBurnie Mary Ann ,   The PAD Trial Investigators
Published: August 2005

Background: The Public Access Defibrillation (PAD) Trial was a randomized, controlled trial designed to measure survival to hospital discharge following out‐of‐hospital cardiac arrest (OOH‐CA) in community facilities trained and equipped to provide PAD, compared with community facilities trained to provide cardiopulmonary resuscitation (CPR) without any capacity for defibrillation. Objectives: To report the implementation of community‐based lay responder emergency response programs in 1,260 participating facilities recruited for the PAD Trial in the United States and Canada. Methods: This was a descriptive study of the characteristics of participating facilities, volunteers, and automated external defibrillator (AED) placements compiled by the PAD Trial, and a qualitative study of factors that facilitated or impeded implementation of emergency lay responder programs using focus groups of PAD Trial site coordinators. Results: The PAD Trial enrolled 1,260 community facilities (14.8% residential), with 20,400 lay volunteers (mean ± standard deviation = 13.4 ± 10.7 per facility) trained to respond to OOH‐CA. The 598 locations randomized to receive AEDs required 2.7 ± 1.8 AEDs per facility. Volunteer attrition was high, 36% after two years. Barriers to recruitment and implementation included identification of appropriate “at‐risk” facilities, lack of interest or fear of litigation by a facility key decision maker, lack of motivated potential volunteer responders, training and retraining resource requirements, and lack of an existing communication/response infrastructure. Conclusions: These data indicate that implementation of community‐based lay responder programs is feasible in many types of facilities, although these programs require substantial resources and commitment, and many barriers to implementation of effective PAD programs exist.
Choosing Outcome Assessment Instruments for Trauma Registries
Authors: Gabbe Belinda J. , Williamson Owen D. , Cameron Peter A. , Dowrick Adam S.
Published: August 2005

While trauma registries have the potential to collect detailed information about patient outcomes, the most commonly reported outcome, mortality, only represents the outcome from a small proportion of the total trauma population. If trauma registries are to progress to routine monitoring of outcomes in trauma survivors, instruments that measure relevant outcomes in the remainder of the trauma population must be identified and implemented. This report provides an overview of the specific needs of trauma registries with respect to assessing patient outcomes other than mortality. The use of previously recommended outcome assessment instruments is discussed, with a focus on the utility of these instruments for use in routine monitoring of trauma outcomes other than mortality through trauma registries.
A System for Grouping Presenting Complaints: The Pediatric Emergency Reason for Visit Clusters
Authors: Gorelick Marc H. , Alpern Elizabeth R. , Alessandrini Evaline A.
Published: August 2005

Objectives: To develop a set of chief complaint groupings for pediatric emergency department (ED) visits that is comprehensive, parsimonious, clinically sensible, and evidence‐based. Methods: Investigators derived candidate chief complaint clusters and ranked them a priori into three perceived severity categories. Pediatric visits were extracted from the National Hospital Ambulatory Medical Care Survey (NHAMCS); data for years 1998 and 2000 (n= 13,186) were used for derivation and data for year 1999 (n= 5,365) were used for validation. Visits were assigned to clusters based on the recorded complaints; clusters were combined to ensure adequate numbers for analysis (minimum n= 20), and the clusters were reviewed for clinical sensibility. Resource utilization was categorized in three levels: routine (examination only), ED treatment (tests or therapy in the ED but not admitted), and admission. Area under the receiver‐operating characteristic (ROC) curve (AUC) was used to demonstrate the discriminative ability of the clusters in predicting resource use. Results: There were 463 unique complaints in the derivation database; 95 (20%) had a single associated visit. Fifty‐two clusters were generated; only 2.4% of complaints were classified as other. The eight most common clusters encompassed 52% of the visits. The top five were fever (11%), extremity pain/injury, vomiting, cough, and trauma (unspecified). Complaint clusters were associated with actual resource utilization: for routine care, the AUC was 0.73 (0.74 in the validation set), and for admission, the AUC was 0.77 (0.74 in the validation set). Both resource utilization and triage classification increased with increased expert severity ranking (test for trend, p < 0.001). Conclusions: The proposed Pediatric Emergency Reason for Visit Cluster (PERC) system is a comprehensive yet parsimonious, clinically sensible means of categorizing pediatric ED complaints. The PERC system's association with measures of acuity and resource utilization makes it a potentially useful tool in epidemiologic and health services research.
Precise Formulation and Evidence‐based Application of Resource‐constrained Triage
Authors: Sacco William J. , Navin D. Michael , Fiedler Katherine E. , Waddell II Robert K. , Long William B. , Buckman Robert F.
Published: August 2005

Objectives: To develop a precise mathematical formulation of resource‐constrained triage, denoted the Sacco triage method (STM), to develop an evidence‐based application to blunt trauma, and to compare the STM with the simple triage and rapid treatment (START) method. Methods: Resource‐constrained triage is modeled mathematically as a classic resource allocation problem. The objective is to maximize expected survivors given constraints on the timing and availability of resources. The model incorporates estimates of time‐dependent victim survival probabilities based on an initial assessment and expected deterioration. For application to blunt trauma, an “RPM” score, based on respiratory rate, pulse rate, and motor response, was used to predict survivability. Logistic function‐generated survival probability estimates for scene values of RPM were determined from 76,459 blunt‐injured patients from the Pennsylvania Trauma Outcome Study (PTOS). The Delphi method provided expert consensus on victim deterioration rates, and the model was solved using linear programming. STM was compared with START across various criteria of process and outcome. Outcome was measured by expected number of survivors in simulated resource‐constrained casualty incidents. Results: In this mathematical simulation, RPM was a more accurate predictor of survivability from blunt trauma than the Injury Severity Score and the Revised Trauma Score, as measured by calibration and discrimination statistics. STM resulted in greater expected survivorship than START in all simulations. Conclusions: Resource‐constrained triage is modeled precisely as an evidence‐based, outcome‐driven method that maximizes expected survivors in consideration of resources. The lifesaving potential and operational advantages over current methods warrant scrutiny and further research.
A Comprehensive, Unembalmed Cadaver‐based Course in Advanced Emergency Procedures for Medical Students
Authors: Tabas Jeffrey A. , Rosenson Jon , Price Daniel D. , Rohde Dana , Baird Carina H. , Dhillon Nripendra
Published: August 2005

Background: Preparing medical students for residency in emergency medicine involves education in many areas of knowledge and skill, including instruction in advanced emergency procedures. Objectives: To outline the logistics involved in running a training course in advanced emergency procedures for fourth‐year medical students and to report students' perceptions of the impact of the course. Methods: The course is a cadaver‐based training laboratory that utilizes several teaching modalities, including a Web‐based syllabus and online streaming video, didactic lecture, hands‐on practice with models and ultrasound, and hands‐on practice with unembalmed (fresh) cadavers. The course focuses on seven emergent procedural skills, including deep venous access via the subclavian, internal jugular, and femoral veins; tube thoracostomy; saphenous vein cutdown; intraosseous line placement; and emergency cricothyrotomy. The course is taught by attending emergency physicians and anatomy department faculty. After completion of the course, students reported their self‐assessments on a five‐point Likert scale. Data were evaluated using a paired t‐test (two‐tailed). Results: Thirty‐three students completed the evaluation. The students reported a mean (± standard deviation [SD]) increase in their understanding of the indications for all procedures from 3.3 (± 1.1) before to 4.8 (± 0.4) after the course (p = 0.004, 95% CI = 0.7 to 2.0). The students reported a mean increase in their understanding of how to perform all procedures from 2.1 (± 0.9) before to 4.6 (± 0.6) after the course (p = 0.003, 95% CI = 1.9 to 3.0). The students reported a mean increase in their comfort level performing all procedures from 1.6 (± 0.8) before to 4.2 (± 0.7) after the course (p < 0.001, 95% CI = 2.0 to 2.9). Conclusions: These findings support the value of an advanced emergency procedural training course using an unembalmed cadaver‐based laboratory and incorporating several teaching modalities.
Father Involvement in Infancy: Influences of Past and Current Relationships
Authors: Shannon Jacqueline D. , Tamis‐LeMonda Catherine S. , Margolin Allan
Published: August 2005

Men's childhood experiences with their parents, their current relationship with their partners, and demographic factors were examined in relation to father‐infant interactions. Participants were 60 racially and ethnically diverse, inner‐city men and their 6‐ to 11‐month‐old infants. Father‐infant interactions were videotaped during semistructured free play in participants' homes. The quality of men's interactions with their infants was assessed using Likert ratings of their responsive‐didactic and negative‐overbearing behaviors. Men engaged in significantly more responsive‐didactic behaviors than negative‐overbearing behaviors. A cumulative score of protective demographic factors (i.e., men residing with their infants, being married, completing high school, and obtaining income above the sample's median level) and men's experiences of childhood acceptance from their fathers uniquely predicted their responsive‐didactic behaviors. Men's relationships with their partners were homogeneously strong and unrelated to fathering behaviors. This study builds on extant literature by providing a broader conceptualization of father‐infant relationships and applying observational methods to the study of fathering in minority, low‐income men.
Endoderm-derived Fgf3 is necessary and sufficient for inducing neurogenesis in the epibranchial placodes in zebrafish
Authors: Nechiporuk Alexei , Linbo Tor , Raible David W.
Published: August 2005

In vertebrates, epibranchial placodes are transient ectodermal thickenings that contribute sensory neurons to the epibranchial ganglia. These ganglia innervate internal organs and transmit information on heart rate, blood pressure and visceral distension from the periphery to the central nervous system. Despite their importance, the molecular mechanisms that govern the induction and neurogenesis of the epibranchial placodes are only now being elucidated. In this study, we demonstrate that endoderm is required for neurogenesis of the zebrafish epibranchial placodes. Mosaic analyses confirm that endoderm is the source of the neurogenic signal. Using a morpholino knockdown approach, we find that fgf3 is required for the majority of placode cells to undergo neurogenesis. Tissue transplants demonstrate that fgf3 activity is specifically required in the endodermal pouches. Furthermore, ectopic fgf3 expression is sufficient for inducing phox2a-positive neurons in wild-type and endoderm-deficient embryos. Surprisingly, ectodermal foxi1 expression, a marker for the epibranchial placode precursors, is present in both endoderm-deficient embryos and fgf3 morphants, indicating that neither endoderm nor Fgf3 is required for initial placode induction. Based on these findings, we propose a model for epibranchial placode development in which Fgf3 is a major endodermal determinant required for epibranchial placode neurogenesis.
Regulation of cellular plasticity inDrosophilaimaginal disc cells by the Polycomb group, trithorax group andlamagenes
Authors: Klebes Ansgar , Sustar Anne , Kechris Katherina , Li Hao , Schubiger Gerold , Kornberg Thomas B.
Published: August 2005

Drosophila imaginal disc cells can switch fates by transdetermining from one determined state to another. We analyzed the expression profiles of cells induced by ectopic Wingless expression to transdetermine from leg to wing by dissecting transdetermined cells and hybridizing probes generated by linear RNA amplification to DNA microarrays. Changes in expression levels implicated a number of genes: lamina ancestor, CG12534 (a gene orthologous to mouse augmenter of liver regeneration), Notch pathway members, and the Polycomb and trithorax groups of chromatin regulators. Functional tests revealed that transdetermination was significantly affected in mutants for lama and seven different PcG and trxG genes. These results validate our methods for expression profiling as a way to analyze developmental programs, and show that modifications to chromatin structure are key to changes in cell fate. Our findings are likely to be relevant to the mechanisms that lead to disease when homologs of Wingless are expressed at abnormal levels and to the manifestation of pluripotency of stem cells.
Hansenula polymorphaPex20p is an oligomer that binds the peroxisomal targeting signal 2 (PTS2)
Authors: Otzen Marleen , Wang Dongyuan , Lunenborg Marcel G. J. , van der Klei Ida J.
Published: August 2005

We have cloned and characterized the Hansenula polymorpha PEX20 gene. The HpPEX20 gene encodes a protein of 309 amino acids (HpPex20p) with a calculated molecular mass of ∼35 kDa. In cells of an HpPEX20 disruption strain, PTS2 proteins were mislocalized to the cytosol, whereas PTS1 matrix protein import proceeded normally. Also, the PTS2 proteins amine oxidase and thiolase were normally assembled and active in these cells, suggesting HpPex20p is not involved in oligomerization/activation of these proteins. Localization studies revealed that HpPex20p is predominantly associated with peroxisomes. Using fluorescence correlation spectroscopy we determined the native molecular mass of purified HpPex20p and binding of a synthetic peptide containing a PTS2 sequence. The data revealed that purified HpPex20p forms oligomers, which specifically bind PTS2-containing peptides.
Upregulation of MMP-9 in MDCK epithelial cell line in response to expression of the Snail transcription factor
Authors: Jordà Mireia , Olmeda David , Vinyals Antònia , Valero Eva , Cubillo Eva , Llorens Ana , Cano Amparo , Fabra Àngels
Published: August 2005

Overexpression of the transcription factor Snail in epithelial MDCK cells promotes the epithelial-mesenchymal transition (EMT) and the acquisition of an invasive phenotype. We report here that the expression of Snail is associated with an increase in the promoter activity and expression of the matrix metalloproteinase MMP-9. The effect of Snail silencing on MMP-9 expression corroborates this finding. Induced transcription of MMP-9 by Snail is driven by a mechanism dependent on the MAPK and phosphoinositide 3-kinase (PI3K) signalling pathways. Although other regions of the promoter were required for a complete stimulation by Snail, a minimal fragment (nucleotides -97 to +114) produces a response following an increased phosphorylation of Sp-1 and either Sp-1 or Ets-1 binding to the GC-box elements contained in this region. The expression of a dominant negative form of MEK decreased these complexes. A moderate increase in the binding of the nuclear factor κB (NFκB) to the upstream region (nucleotide -562) of the MMP-9 promoter was also observed in Snail-expressing cells. Interestingly, oncogenic H-Ras (RasV12) synergistically co-operates with Snail in the induction of MMP-9 transcription and expression. Altogether, these results indicate that MMP-9 transcription is activated in response to Snail expression and that it might explain, at least in part, the invasive properties of the Snail-expressing cells.
Tumour necrosis factor α confers an invasive, transformed phenotype on mammary epithelial cells
Authors: Montesano Roberto , Soulié Priscilla , Eble Johannes A. , Carrozzino Fabio
Published: August 2005

Although loss of cell-cell adhesion and gain of invasive properties play a crucial role in the malignant progression of epithelial tumours, the molecular signals that trigger these processes have not been fully elucidated. In light of the well-established relationship between chronic inflammation and cancer, we hypothesized that pro-inflammatory cytokines disrupt epithelial-cell adhesion and promote cell migration. To test this hypothesis, we used an in vitro model in which 31EG4-2A4 mouse mammary epithelial cells grown in a collagen gel form compact spheroidal colonies. Among the several cytokines examined, tumour necrosis factor α (TNF-α) caused a pronounced 3D scattering of preformed epithelial-cell colonies and induced 31EG4-2A4 cells grown on top of a collagen gel to invade the underlying matrix. In addition, TNF-α abolished contact-mediated inhibition of cell proliferation and stimulated cell growth both in the absence of exogenous mitogens and under anchorage-independent conditions. TNF-α induced the expression of matrix metalloproteinase 9 (MMP-9). Addition of the MMP inhibitor BB-94 abrogated TNF-α-induced 3D scattering. TNF-α also enhanced the attachment of 31EG4-2A4 cells to type-I collagen and markedly increased the expression of the α2 integrin subunit. Addition of a blocking antibody to β1-integrin or of rhodocetin (a specific α2β1 antagonist) to collagen-gel cultures abrogated 3D scattering. Collectively, these results demonstrate an essential role for MMPs and α2β1 integrin in the invasive response of 31EG4-2A4 cells to TNF-α. We propose that the biological activities described in this study contribute to the ability of TNF-α to promote tumour progression and cancer-cell dissemination.
The lysosomal cysteine protease cathepsin L regulates keratinocyte proliferation by control of growth factor recycling
Authors: Reinheckel Thomas , Hagemann Sascha , Dollwet-Mack Susanne , Martinez Elke , Lohmüller Tobias , Zlatkovic Gordana , Tobin Desmond J. , Maas-Szabowski Nicole , Peters Christoph
Published: August 2005

Mice deficient for cathepsin L (CTSL) show epidermal hyperplasia due to a hyperproliferation of basal keratinocytes. Here we show that the critical function of CTSL in the skin is keratinocyte specific. This is revealed by transgenic re-expression of CTSL in the keratinocytes of ctsl-/- mice, resulting in a rescue of the ctsl-/- skin phenotype. Cultivation of primary mouse keratinocytes with fibroblast- and keratinocyte-conditioned media, as well as heterologous organotypic co-cultures of mouse fibroblasts and human keratinocytes, showed that the altered keratinocyte proliferation is caused primarily by CTSL-deficiency in keratinocytes. In the absence of EGF, wild type and CTSL-knockout keratinocytes proliferate with the same rates, while in presence of EGF, ctsl-/- keratinocytes showed enhanced proliferation compared with controls. Internalization and degradation of radioactively labeled EGF was identical in both ctsl-/- and ctsl+/+ keratinocytes. However, ctsl-/- keratinocytes recycled more EGF to the cell surface, where it is bound to the EGF-receptor, which is also more abundant in ctsl-/- cells. We conclude that the hyperproliferation of keratinocytes in CTSL-knockout mice is caused by an enhanced recycling of growth factors and growth factor receptors from the endosomes to the keratinocyte plasma membrane, which result in sustained growth stimulation.
Dynein light chain rp3 acts as a nuclear matrix-associated transcriptional modulator in a dynein-independent pathway
Authors: Yeh Ting-Yu , Chuang Jen-Zen , Sung Ching-Hwa
Published: August 2005

Cytoplasmic dynein is a motor protein complex involved in microtubule-based cargo movement. Previous biochemical evidence suggests that dynein light chain subunits also exist outside the dynein complex. Here we show that the dynein light chain rp3 is present in both the cytoplasm and the nucleus. Nuclear rp3 binds to and assembles with the transcription factor SATB1 at nuclear matrix-associated structures. Dynein intermediate chain was also detected in the nucleus, but it was dispensable for the rp3-SATB1 interaction. SATB1 facilitates the nuclear localization of rp3, whereas rp3 and dynein motor activity are not essential for nuclear accumulation of SATB1. The nuclear rp3-SATB1 protein complex is assembled with a DNA element of the matrix attachment region of the Bcl2 gene. Finally, rp3 is involved in SATB1-mediated gene repression of Bcl2. Our data provide evidence that dynein subunit rp3 has functions independent of the dynein motor.
Wounding activates p38 map kinase and activation transcription factor 3 in leading keratinocytes
Authors: Harper Erin G. , Alvares Stacy M. , Carter William G.
Published: August 2005

Quiescent epidermis anchors to laminin 5 in the basement membrane via integrin α6β4. Wounding elevates expression of laminin 5, generating leading keratinocytes (LKs) that migrate via β1 integrins. Laminin 5 was evaluated as a regulator of cell signaling, and mRNA and protein expression in LKs. An in vitro wound model was developed based on suspension and re-adhesion of quiescent human keratinocytes (HKs). DNA microarrays identified multiple mRNAs elevated 1.5 hours after suspension and re-adhesion including activation transcription factor 3 (ATF3). In vitro and in vivo, levels of ATF3 protein elevate in nuclei of LKs, but not in nuclei of the following cells, 2 hours after suspension or wounding but decline by 12-18 hours post injury. Significantly, null defects in laminin 5 or integrin β4 that inhibit anchorage chronically elevate ATF3 in vivo. This suggests that adhesion to laminin 5, but not other ligands, suppresses activation. On suspension, ATF3 and other transcripts in the microarrays are elevated by phosphorylated p38 mitogen-activated protein kinase (P-p38), a stress kinase that regulates mRNA and cell motility. Inhibition of P-p38 with SB203580 prevents phosphorylation of ATF2, a transcription factor for ATF3 in LKs. Re-adhesion to laminin 5 via α6β4 dephosphorylates P-p38 and suppresses ATF3 protein relative to cells in suspension. Thus, wounding of quiescent HKs disrupts laminin 5 adhesion to activate p38, generating mRNA transcripts that define LKs. Adhesion to deposits of laminin 5 via α6β4 suppresses P-p38 and activation mRNAs including ATF3. Defects in laminin 5 and α6β4 sustain P-p38 with probable pathological effects on transcription and migration.
Abl tyrosine kinase regulates a Rac/JNK and a Rac/Nox pathway for DNA synthesis and Myc expression induced by growth factors
Authors: Boureux Anthony , Furstoss Olivia , Simon Valérie , Roche Serge
Published: August 2005

The cytoplasmic tyrosine kinase Abl is a Src substrate required for platelet-derived growth factor (PDGF) receptor signaling leading to Myc expression and DNA synthesis. Abl targets are, however, ill defined. Here we report that the small GTPase Rac is an important effector of its mitogenic function. PDGF-induced Rac activation was impaired in cells with inactive Abl and active Rac overcame the mitogenic defects found in these cells. Rac function required both a Jun N-terminal kinase (JNK) and a NADPH oxidase (Nox) pathway. Furthermore, co-activation of JNK and Nox were sufficient to mimic the Rac mitogenic rescue. Abl also regulated PDGF-induced JNK and Nox activation. Finally, we found that Myc is an important target of this signaling cascade: Myc induction was sensitive to small inhibitors of JNK and Nox activities and forced expression of Myc overcame the G1 block induced by dominant interfering mutants of mitogen-activated protein kinase kinase 4 (MKK4) and Nox2 activating subunit. We concluded that cytoplasmic Abl operates on a Rac/JNK and a Rac/Nox pathway for PDGF-induced Myc induction and DNA synthesis.
Microtubule actin crosslinking factor 1b: a novel plakin that localizes to the Golgi complex
Authors: Lin Chung-Ming , Chen Hui-Jye , Leung Conrad L. , Parry David A. D. , Liem Ronald K. H.
Published: August 2005

MACF1 (microtubule actin crosslinking factor), also called ACF7 (actin crosslinking family 7) is a cytoskeletal linker protein that can associate with both actin filaments and microtubules. We have identified a novel alternatively spliced isoform of MACF1. We named this isoform MACF1b and renamed the original isoform MACF1a. MACF1b is identical to MACF1a, except that it has a region containing plakin (or plectin) repeats in the middle of the molecule. MACF1b is ubiquitously expressed in adult tissues with especially high levels in the lung. We studied the subcellular localization of MACF1b proteins in mammalian cell lines. In two lung cell lines, MACF1b was chiefly localized to the Golgi complex. Upon treatments that disrupt the Golgi complex, MACF1b redistributed into the cytosol, but remained co-localized with the dispersed Golgi ministacks. MACF1b proteins can be detected in the enriched Golgi fraction by western blotting. The domain of MACF1b that targets it to the Golgi was found at the N-terminal part of the region that contains the plakin repeats. Reducing the level of MACF1 proteins by small-interfering RNA resulted in the dispersal of the Golgi complex.
Three-dimensional study of separated flow over a square cylinder by large eddy simulation
Authors: Farhadi M , Rahnama M
Published: August 2005

Large eddy simulation of flow over a square cylinder in a channel is performed at Reynolds numbers of 22 000 and 21 400. The selective structure function (SSF) modelling of the subgrid-scale stress terms is used and the convective terms are discretized using quadratic upstream interpolation for convective kinematics (QUICK) and central difference (CD) schemes. A series of time-averaged velocities, turbulent stresses, and some global flow parameters such as lift and drag coefficients and their fluctuations are computed and compared with experimental data. The suitability of SSF model has been shown by comparing the computed mean flow velocities and turbulent quantities with experiments. Results show negligible variation in the flow parameters for the two Reynolds numbers used in the present computations. It was observed that both QUICK and CD schemes are capable of obtaining results close to those of the experiments with some minor differences.
An Analysis of the Alias Method for Discrete Random-Variate Generation
Authors: Smith J. Cole , Jacobson Sheldon H.
Published: August 2005

This paper introduces and studies an optimization problem related to the alias method for discrete random-variate generation. The alias method is an efficient method to generate random variates from a discrete probability distribution. The efficiency of the alias method can be improved by designing the alias table such that the expected number of computations that must be performed per value generated is minimized. The problem of optimizing the construction of the alias table is proven to be strongly NP-hard, even if either of two variations of the alias method relaxing the alias-table-generation restrictions are used. Integer-programming formulations describing these three optimization problems are presented, and insights regarding necessary optimality criteria and relationships among their optimal solutions are discussed.
Lower Bounds for the Head-Body-Tail Problem on Parallel Machines: A Computational Study of the Multiprocessor Flow Shop
Authors: Vandevelde Ann , Hoogeveen Han , Hurkens Cor , Lenstra Jan Karel
Published: August 2005

The multiprocessor flow-shop is the generalization of the flow-shop in which each machine is replaced by a set of identical machines. As finding a minimum-length schedule is NP-hard, we set out to find good lower and upper bounds. The lower bounds are based on relaxation of the capacities of all machine sets except one. This results in a parallel-machine scheduling problem with release dates and delivery times, for which we derive a number of lower bounds. We pay special attention to the time complexity of algorithms for computing these bounds. To obtain the upper bounds a constructive algorithm in subsequent stages is used. We present an experimental comparison of the various lower and upper bounds for the multiprocessor flow-shop problem.
Ethnic Disparities: Control of Glycemia, Blood Pressure, and LDL Cholesterol Among US Adults with Type 2 Diabetes
Authors: Kirk Julienne K , Bell Ronny A , Bertoni Alain G , Arcury Thomas A , Quandt Sara A , Goff David C , Narayan K M Venkat
Published: August 2005

OBJECTIVE:

To examine ethnic disparities in the quality of diabetes care among adults with diabetes in the US through a systematic qualitative review.

DATA SOURCES:

Material published in the English language was searched from 1993 through June 2003 using PubMed, Web of Science, Cumulative Index to Nursing and Allied Health, the Cochrane Library, Combined Health Information Database, and Education Resources Information Center.

STUDY SELECTION AND DATA EXTRACTION:

Studies of patients with diabetes in which at least 50% of study participants were ethnic minorities and studies that made ethnic group comparisons were eligible. Research on individuals having prediabetes, those <18 years of age, or women with gestational diabetes were excluded. Reviewers used a reproducible search strategy. A standardized abstraction and grading of articles for publication source and content were used. Data on glycemia, blood pressure, and low-density lipoprotein cholesterol (LDL-C) were extracted in patients with diabetes. A total of 390 studies were reviewed, with 78 meeting inclusion criteria.

DATA SYNTHESIS:

Ethnic minorities had poorer outcomes of care than non-Hispanic whites. These disparities were most pronounced for glycemic control and least evident for LDL-C control. Most studies showed blood pressure to be poorly controlled among ethnic minorities.

CONCLUSIONS:

Control of risk factors for diabetes (glycemia, blood pressure, LDL-C) is challenging and requires routine assessment. These findings indicate that additional efforts are needed to promote diabetes quality of care among minority populations.
Coherent Anti-Stokes Raman Spectroscopy of Water Vapor for Combustion Diagnostics
Authors: Hall Robert J. , Shirley John A.
Published: August 2005

The coherent anti-Stokes Raman spectroscopy spectrum of H2O has been measured in a heated optical cell and in laboratory flames. Comparisons of the experimental spectra with a theoretical model have been used to infer information about the unknown Raman linewidths of H2O. In the test cell, excellent agreement has been obtained between theory and experiment in terms of physically realistic linewidths. Agreement between experiment and theory in laboratory flames is also good.
Industrial Applications of a Capillary Gas Chromatography/Fourier Transform Infrared System
Authors: Smith S. L. , Garlock S. E. , Adams G. E.
Published: August 2005

In this work, we describe the interfacing of a high-resolution chromatographic system featuring narrow bore gas chromatographic columns to a Fourier transform infrared spectrometer. Excellent chromatographic resolution, low nanogram sensitivity, and compound identification are demonstrated. Applications to the analysis of a petroleum distillation fraction and to a polymer sample, analyzed after pyrolysis, are presented. A vapor-phase library search system is used to identify compounds in both samples.
The Determination of Some Trace Elements in Uranium by Inductively Coupled Plasma Emission Spectroscopy Using a Graphite Rod Sample Introduction Technique
Authors: Kirkbright G. F. , Snook R. D.
Published: August 2005

Studies of the determination of Ag, Be, Cd, Zn, Cu, Fe, Cr, and Al in the presence of uranium(VI) by optical emission spectroscopy with an inductively coupled argon plasma source and electrothermal vaporization of 10-μl solution samples using a graphite rod are described.
The Resolution Enhancement of Electron Spin Resonance Spectra by Self-Deconvolution with a Finite Impulse Response Operator
Authors: Shimokoshi Kazuo , Jones R. Norman
Published: August 2005

The method of self-deconvolution is applied to the resolution enhancement of electron spin resonance spectra (ESR). The component lineshapes of ESR spectra are basically Lorentzian, but they often carry strong Gaussian perturbations. Deconvolution with a finite impulse response operator filter to enhance the resolution of Lorentzian and Gaussian ESR band envelopes is discussed and a more general function is derived for Gauss-Lorentz convolute (Voigt) lineshapes. The method is applied initially to the simulated isotropic ESR spectrum of the ethyl radical in the liquid state and to a simulated anisotropic spectrum of a crystalline powder. Application to real spectra is illustrated by the anisotropic spectrum of bis(acetylacetonato)-copper(II) [Cu(AcAc)2] in ethanol solution at 140 K in order to resolve the hyperfine lines. The perpendicular component of this spectrum is notable for its poor resolution.
Dual Laser Ionization in Flames: A Search for Electrical Interferences
Authors: Curran F. M. , VanDijk C. A. , Crouch S. R.
Published: August 2005

Experimental studies of electrical interferences in the dual laser ionization technique are reported and compared to those commonly encountered in laser-enhanced ionization spectrometry. For the dual laser ionization of sodium, the addition of easily ionized matrix components such as cesium, lithium, and potassium were found to have little or no effect on signal recovery. Similar results were obtained in experiments with lithium and strontium as the analytes. Some chemical interferences were found and discussed.
Design Modification for a Uniform Droplet Generator System
Authors: Seymour Robert J. , Boss Charles B.
Published: August 2005

Design modifications are presented for a uniform size and trajectory droplet generator useful for the study of interferences and other phenomena in analytical flames. The new design produces stable droplets without drift in size or trajectory and allows adjustment in the drop size by changing the drop production frequency without manual adjustment of the introduction rate timing circuit associated with previous designs. The control circuitry in this design uses easily obtainable and inexpensive digital and analog components. Details of the electronics and mechanical apparatus are included and performance characteristics are discussed.
The Application of Fast Fourier Transform and Convolution Techniques to Picosecond Continuum Spectroscopy
Authors: Sala K. L. , Yip R. W. , LeSage R.
Published: August 2005

The use of the fast Fourier transform in the processing of photographic data obtained from picosecond continuum spectroscopy is described. The resulting reduction in the complexity and computation time has permitted all of the data acquisition and processing to be carried out with an eight-bit microcomputer. Specific examples of some key problems in the data processing that are peculiar to this spectroscopic technique and methods of overcoming these problems are discussed. Experimental results that serve to illustrate both the experimental technique itself as well as the versatility and reliability of the data processing algorithm are presented for the transient absorption of a Cr(III) complex in solutions.
The Determination of Trace Amounts of Tin by Inductively Coupled Argon Plasma Atomic Emission Spectrometry with Volatile Hydride Method
Authors: Nakahara Taketoshi
Published: August 2005

A sensitive method is described for the determination of trace amounts of tin, based on continuous sodium borohydride reduction of tin in solution to gaseous stannane. The stannane generated is introduced into a relatively low-powered (1.6 kW) inductively coupled argon plasma source. The effects of a range of acids and interelement effects are investigated. Mixtures of nitric and succinic acids and of nitric and malic acids are the most suitable reaction media, especially in the presence of interferents. The method of standard additions is recommended for accurate tin determination. Compared to a conventional solution nebulization, the present system gives a sensitivity increase of a factor of approximately 3 orders of magnitude. The detection limit for tin is 0.05 ng/ml and precision values at 20 and 50 ng/ml Sn are less than 3% relative standard deviation. The linear calibration range spans nearly 5 orders of magnitude. The proposed method is applied to the determination of tin in low alloyed steels and in National Bureau of Standards standard reference materials (Cu-Ni alloy, orchard leaves, wheat flour, and rice flour).
Intra-Alkali Matrix Effects in the Inductively Coupled Plasma
Authors: Faires Lynda M. , Apel Charles T. , Niemczyk Thomas M.
Published: August 2005

Spatial profile studies are used to determine the interference effects of alkali matrix elements on the observed emission of alkali analyte elements in the inductively coupled plasma. These interferences are referred to as intra-alkali matrix effects. It is found that significant enhancement of the analyte emission occurs low in the plasma in the initial radiation zone where atomic emission is most intense and that a slight downward shift in the vertical position of the emission peak is caused by the presence of the alkali matrix. A “same value” point occurs in the normal analytical zone where no net effect of the matrix on analyte emission is apparent. In the tail plume of the plasma, some lesser enhancement is again observed. The magnitude of the enhancement effect increases as the ionization potential of the matrix element decreases, and the effect appears linear with matrix concentration. The data suggest that the interference mechanism is related to an increase in electron density in the lower region of the plasma, and analytical correction for the interference is recommended for alkali determinations in the inductively coupled plasma.
A Study for N2 Coherent Anti-Stokes Raman Spectroscopy Thermometry at High Pressure
Authors: Kataoka Haruhiko , Maeda Shiro , Hirose Chiaki , Kajiyama Koichi
Published: August 2005

N2 coherent anti-Stokes Raman spectroscopy (CARS) thermometry over a pressure range 1 to 50 atm has been studied. The CARS profile at high pressure and high temperature was recorded by using the ignition inside a running engine cylinder. The observed Q-branch profile was theoretically fitted by incorporating the collisional narrowing effect, serving for the temperature determination at various pressures. Because of the narrowing effect, the apparent band width showed little change with pressure above 5 atm in general. It has been suggested that the band width at 1/5 of the maximum height can be a useful measure of temperature, while the usual half-width turns out to be hardly practicable at high pressures.
Mass Spectra and Ionization Temperatures in an Argon-Nitrogen Inductively Coupled Plasma
Authors: Houk Robert S. , Montaser Akbar , Fassel Velmer A.
Published: August 2005

Positive ions were extracted from the axial channel of an inductively coupled plasma (ICP) in which the outer gas flow was Ar, N2, or a mixture of Ar and N2. Addition of N2 to the outer gas decreases the electron number density ( ne) in the axial channel. Ar+2, O2+, and ArH+ react with N-containing species in the plasma and/or during the ion extraction process. Ar+ remains abundant even if there is no Ar in the outer gas, which indicates the probable occurrence of charge transfer reactions between N2+ and Ar. The present work corroborates two general concepts upon which several theories of the origin of suprathermal ionization in ICPs are based: (a) species are physically transported from the induction region to the axial channel; and (b) these species may react with and ionize neutral species in the axial channel. Ionization temperatures ( Tion) measured from the ratio Cd+/I+ were 5750 to 6700 K for a N2 outer flow ICP at a forward power of 1.2 kW. This Tion range is significantly below that obtained for an Ar outer gas ICP under otherwise similar operating parameters.
Temporal Patterns of Fos Expression in the Dentate Gyrus after Spontaneous Seizures in a Mouse Model of Temporal Lobe Epilepsy
Authors: Peng Zechun , Houser Carolyn R.
Published: August 2005

Identifying the brain regions and neuronal cell types that become active at the time of spontaneous seizures remains an important challenge for epilepsy research, and the involvement of dentate granule cells in early seizure events continues to be debated. Although Fos expression is commonly used to evaluate patterns of neuronal activation, there have been few studies of Fos localization after spontaneous seizures. Thus, in a pilocarpine model of recurrent seizures in C57BL/6 mice, Fos expression was examined at multiple time points after spontaneous seizures to follow the temporal and spatial patterns of Fos activation. By 15 min after the beginning of a spontaneous behavioral seizure, Fos labeling was evident in dentate granule cells. This labeling was particularly striking because of its wide extent and relatively uniform appearance in the granule cell layer. At later time points, from 30 min to 4 h after a spontaneous seizure, Fos labeling was also detected in interneurons within the dentate gyrus and in widespread regions of the temporal lobe. Interestingly, the timing of Fos activation appeared to differ among different types of GABAergic interneurons in the dentate gyrus, with labeling of parvalbumin neurons along the base of the granule cell layer preceding that of GABA neurons in the molecular layer. The findings in this mouse model are consistent with previous suggestions that spontaneous seizures in temporal lobe epilepsy may result from a periodic breakdown of the normal filter functions of the dentate gyrus and a resulting increase in hypersynchronous activity of dentate granule cells.
The Human Hippocampus: Cognitive Maps or Relational Memory?
Authors: Kumaran Dharshan , Maguire Eleanor A.
Published: August 2005

The hippocampus is widely accepted to play a pivotal role in memory. Two influential theories offer competing accounts of its fundamental operating mechanism. The cognitive map theory posits a special role in mapping large-scale space, whereas the relational theory argues it supports amodal relational processing. Here, we pit the two theories against each other using a novel paradigm in which the relational processing involved in navigating in a city was matched with similar navigational and relational processing demands in a nonspatial (social) domain. During functional magnetic resonance imaging, participants determined the optimal route either between friends' homes or between the friends themselves using social connections. Separate brain networks were engaged preferentially during the two tasks, with hippocampal activation driven only by spatial relational processing. We conclude that the human hippocampus appears to have a bias toward the processing of spatial relationships, in accordance with the cognitive map theory. Our results both advance our understanding of the nature of the hippocampal contribution to memory and provide insights into how social networks are instantiated at the neural level.
The mRNA for Elongation Factor 1α Is Localized in Dendrites and Translated in Response to Treatments That Induce Long-Term Depression
Authors: Huang Fen , Chotiner Jennifer K. , Steward Oswald
Published: August 2005

There is increasing evidence that long-lasting forms of activity-dependent synaptic plasticity, such as long-term potentiation (LTP) and long-term depression (LTD), require local synthesis of proteins within dendrites. Identifying novel dendritic mRNAs and determining how their distribution and translation is regulated is a high priority. We demonstrate here that the mRNA for the elongation factor 1 α (EF1α) is presentin vivoin the dendrites of neurons that exhibit LTP and LTD, and that its translation is locally regulated. The subcellular distribution of EF1α mRNA differs from any of the dendritic mRNAs that have been described previously. In the hippocampus, the mRNA is highly expressed in cell bodies and is also concentrated in the zone of termination of commissural/associational afferents in the inner molecular layer, suggesting that mRNA localization is in some way related to the distribution of different types of synapses. Nevertheless, the localization of EF1α mRNA is not altered by prolonged periods of synaptic activation that are sufficient to cause a dramatic redistribution of Arc mRNA. Local application of the metabotropic glutamate receptor agonist (R,S)-3,5-dihydroxyphenylglycine (DHPG) led to dramatic increases in immunostaining for EF1α protein in dendrites, and treatment of hippocampal slices with DHPG, which is known to induce LTD, led to increases in EF1α protein levels. Both responses were blocked by the protein synthesis inhibitor anisomycin. In contrast, stimulation of the perforant path using patterns of stimulation that induce LTP caused rapid increases of immunostaining for EF1α protein in the activated dendritic lamina, but these increases were not blocked by anisomycin or rapamycin. The findings suggest that local synthesis of EF1α protein may be important for the synaptic mechanisms that underlie protein synthesis-dependent LTD.
The Caudal Migratory Stream: A Novel Migratory Stream of Interneurons Derived from the Caudal Ganglionic Eminence in the Developing Mouse Forebrain
Authors: Yozu Masato , Tabata Hidenori , Nakajima Kazunori
Published: August 2005

The migratory paths of interneurons derived from the ganglionic eminence (GE), and particularly its caudal portion (CGE), remain essentially unknown. To clarify the three-dimensional migration profile of interneurons derived from each part of the GE, we developed a technique involving focal electroporation into a small, defined portion of the telencephalic hemisphere. While the medial GE cells migrated laterally and spread widely throughout the cortex, the majority of the CGE cells migrated caudally toward the caudal-most end of the telencephalon. Time-lapse imaging and anin vivoimmunohistochemical study confirmed the existence of a migratory stream depicted by a population of CGE cells directed caudally that eventually reached the hippocampus. Transplantation experiments suggested that the caudal direction of migration of the CGE cells was intrinsically determined as early as embryonic day 13.5. The caudal migratory stream is a novel migratory path for a population of CGE-derived interneurons passing from the subpallium to the hippocampus.